Gravid i Norge 2016 100 000 graviditeter i Norge Perinatal dødlighet

Transcription

Gravid i Norge 2016 100 000 graviditeter i Norge Perinatal dødlighet
100 000 graviditeter i Norge
Gravid i Norge 2016
Spontan abort
Ekstrauterint svangerskap
15 000
1500
Fødsel
spontan abort
indusert abort
Fødsel
EX uterint60
ssk000
Babill Stray-Pedersen
Indusert abort
Prof I em.
15 000
Kvinneklinikken, Rikshospitalet
Oslo Universitetssykehus
og
Universitet i Oslo
Norge
Antall fødte 2014:
Gravid i Norge
60 026
Gutt 51.4% - Pike 48.6%
Antall barn per kvinne:
1.84
52 fødeinstitusjoner
21 neonatal enheter
20 % født uten
neonatal service
Lav spebarns dødlighet < 7d:
> 28 uker:
>22 uker:
2.8 av 1000
4.3 av 1000
Best i verden
Foreldrepermisjon (49 / 59 uker)
Mamma må ta 10 uker ( 3+7)
Pappa
må ta 10 uker
+ 5 uker per barn > 1
Amme permisjon: 2 t (1t) per dag
Komplikasjoner
I svangerskapet:
Alder:
30.6 år
1. gangs fødende:
26 - 31 år (28.7)
20 % Far: 35%
3%
6%
> 35 år:
< 20 år:
4 eller flere barn:
1 av 4, stiger med alder
Ved fødsel:
1 av 3 , stiger med alder
For tidlig fødsel:
1 av 15
“Fjernkulturelle”:
1 av 6 ( 12%)
0.5-1.5 kg 1% (ca 600 barn)
( Oslo 1 av 4)
Eldre mor
Mødre og spebarnsdødlighet
I Norge
Antall fødsler
Mor død
perinatal
død
per 1000
Fødsler
70 000
107
100
60 000
20
21
40 000
47
Mor død
17
Perinatal død
1950
1960
10
11
14
5
1940
50
8
5
1970
Fødsels
register
1980
1990
Perinatal
komite
4
64
2000
Retninglinjer
Perinatal dødlighet i Norge
Mor er eldre i Norge idag
Perinatale
dødlighet
Downs
syndrom
Mors
dødlighet
6 per 1000
4 per 10 000
40 år: 20 per 1000
100 per 10 000
20
45 år: 30 per 1000
400 per 10 000
100
RR
23 år:
2010
191 dødfødte
3 per 1000
Biologiske klokke tikker
Dødfødte etter 22 uke er halvert siden 1999
Risk of Maternal Death during Lifetime
1 : 140
Mødre dødlighet i Norge
Per 1000
kvinner
1/ 7600
10
blødning
1/ 2400
5
1/ 11
barselsfeber
1
1
1/12000
1/ 120
1/ 31
Keisersnitt
1/ 190
1/240
1/ 7400
Penicillin
Blod overføring
0,1
Tidlig mobilisering
1750
1800 1850
1900
1950
2000
UN, 2008
År
Mødre dødlighet i Norge
Maternal Mortality 2005
Betydningen av mors alder
Direct causes per 100 000
74.2
75
70
Per 100 000 fødsler
Hungary
11.9
France
11.3
Finland
9.9
Denmark
9.8
Austria
9.4
Portugal
9.0
Netherlands 7.7
UK
6.9
Belgium
4.7
Norway
4.5
1971-80
19.0
20
15
10.3
10
5
4.1 4.5
5.0
0
<20
20-24 25-29 30-34 35-39
>40
Alders-spesifikk mødredødelighets-rate
S.Vangen
Hva har skjedd de siste 45 år ?
Alvorlig syklighet hos mor ved fødsel
Fertilitet (barn perkvinne)
Oslo: 1-2 av 100 kvinner
1/3 kan velges ut på forhånd
2/3 kommer helt uventet
= 6 per 1000 fødsler
= 1 per 150 fødsler
Den norske mor barn undersøkelsen
MoBa
• Inkludert 100 000 svangerskap 2008.
1967
2012
3.0
1.8
Alder på førstegangsfødende 21
29 år
4 eller flere barn
15 %
6%
Svangerskaps permisjon
12
49 u
For tidlig fødsel
6.5 %
6 %
under 28 uker
0.7%
1.8 %
Keisersnitt
2.2
17 %
Spebarnsdødlighet
20
5
Bekkenløsning
• 15 % mente de hadde bekkenleddsyndrom.
• 2,5 % mente å ha alvorlig grad
• 7,7 % av de gravide brukte krykker pga smertene.
Risikoen for BL økte med antall tidligere fødsler:
• 11 % av de førstegangsfødende
– 18 % av de andregangsfødende
• Mor, far , barn
• 21 % av de tredjegangsfødende.
• 100 subprosjekter
• Risikoen for alvorlig BL var
• 3 ganger økt for 3 gangsfødende
– sammenlignet med førstegangsfødende, justert for andre faktorer.
Preterm fødsel
MFR: 900 000 barn født > 23 uker 1967-1983
USA
USA
Norge
IVF
Sammenheng mellom
12,5 %
avtagende svangerskapslengde og økt forekomst av
5%
9
8
• cerebral parese,
7
6
%
5
• psykisk utviklingshemning
4
3
2
• flere andre funksjonshemninger,
1
0
1980
1990
2000
Year
• andel med uførepensjon som voksne.
7,6
7,5
7,4
Belgia:
7,3
7,6 %
7,2
7,1
7
Moster et al, N Eng J Med 2008
6,9
6,8
1995
2000
2002
2004
Assistert befruktning 2.9 % : 2000 / år
totalt 32 000 barn
Flerfødsler i Norge
2%
6000 IVF fødsler
1,6%
Twins
24%
Triplets etc
3%
Barn: IVF - naturlig befruktning (2500 barn)
• 25 gram lavere fødselsvekt,
• 2 dager tidligere
• 31 % høyere risiko for dødfødsel
Romundstad, Lancet 2008
Fødsels fakta i Norge
Fødsel
• Økende alder på mor
Overtid 41 og > 42 uker
• Diabetes
• Overtid > 42uker
3%
• Barnet s vekt
Fødselsvekt 1967- 2014
• Dobbling av tvillinger 
• Økende keisersnitt –
3500g
Totalt
Hjemme:
stabilt siste år
60 000
153p + 195
Transport 125
Keisersnitt: 10 000
Induksjon18 %
Epidural 34 %
Operativ vaginal fødsel 9 %
Keisersnitt
Vacuum 9 %
10 700
Tang 1,5%
Episiotomi
16.5 %
Manuell uth.placenta 1%
Perineal rift 3- 4
2,5%
Keisersnitt i Norge 1967-2009
Mors alder
Keisersnitt i Norge 1967-2011
17,1%
> 35 yrs
Total
< 20 yrs
Norgeshelsa‐FHI
Komplikasjons risikoen ved keisersnitt øker ved
Indikasjon - årsak 2778 pas i Norge
Fosterstress (tegn på oksygenmangel)
Langsom framgang
Tidligere keisersnitt
Seteleie etter 34. svangerskapsuke
Mors ønske
Svangerskapsforgiftning
Mislykket igangsetting av fødsel
Andre indikasjoner
608
248
234
172
112
602
%
22
21
9
8
8
6
4
22
•
ikke planlagt keisersnitt (38%
•
gestasjons alder < 30 uker
•
stort foster
•
generell anestesi
•
cervix dilatasjon
0 cm:
versus
18%)
16%
9-10cm:
33%
Am J Ob Gyn. 2004;190:428-34.
Vaginal fødsel etter keisersnitt VABAC
•
Velykket opp til 85%
Kolaas T et al, 2003
•
Amming i Norge
Ruptur :
0,5 - 1,5 % ( normal fødsel - induksjon)
Svangerskapsomsorgen i Norge
1 uke
6mnd
1984
1995
2006
12mnd
Perinatal komiteer
Jordmor i hver komune
EB medisin
Kunnskapsbasert
De nye retningslinjer
Risiko for foster
• Informasjon til kvinnen, velge selv
Velge lege/jordmor:
samme person
• Røyk
• Alt er tilbud. (syfilis, HIV, ultralyd)
• Alkohol
• Færre kontroller ( 7-8 )
– Ikke gyn us, kun på indikasjon
– Spør om liv – ikke alltid lytte på fosterlyd
– Ikke barsels 6 ukers kontroll
• Infeksjoner
Røyking
Mor røyker
Norway:
< 20år:
1.svangerskapskontroll
7% røker tidlig I svangerskapet  4% siste kontroll
19 %
 10 %
Behandling i svangerskapet
Diskusjon i dag
Før svangerskapet –
Prekonsepsjonell undersøkelse og veiledning
• Medisinen skal være:
Kvinner > 38 år,
•
•
•
•
sikker for fosteret
effektiv
anvendes i kortest mulig tid
dosering: identisk eller høyere enn
normal dose
Kvinner med fedme
KMI > 35: 4%
Kvinner med sykdom, bruker medikamenter
Tidligere født sykt barn
Risikofylt arbeid : reiser, tungt fysisk arbeid
Folinsyre 76% - livsstil
• Kvinnens egne varianter:
• Myk fødsel hjemme , alternativ fødestue
Se Legemiddelhåndboken
FASS
• Keisersnitt på eget ønske
• Hindre for tidlig fødsel
Vi skal gjennomgå
forandringer i:
Hva skjer’a?
•
•
•
•
•
Mors fysiologi under graviditet
18. Januar 2016
Kurs O- 30576: Obstetrikk
Hvorfor skjer det?
Anne Cathrine (Annetine) Staff
Professor I
Det medisinske fakultet
Universitetet i Oslo
Overlege,
Kvinneklinikken
Oslo universitetssykehus
•
•
•
Viktig for å forstå fysiologiske
forandringer i svangerskapet:
Placenta viktigste årsak til endringer: essensiell for normal og patologisk
svangerskapsutvikling
Intet klart skille mellom «normal» og «patologisk» fysiologi i
svangerskapet?
Samspill kvinnen og fosterceller: essensielt for placentering og
placentafunksjon og svangerskapshelse
Store metabolske forandringer i svangerskapet
Maternell anabolsk metabolisme tidlig i graviditeten:
lagrer næringsstoffer for senere behov
(økt fettvev ila første halvdel av svangerskapet: 3.5 kg ca)
• Svangerskapet preges av en arteriovenøs shunt
Maternell katabolisme i 3. trimester:
• Shunter næringsstoffer til raskt voksende foster
• Støtter fosterets svære anabolske vekst
– Uteroplacentær sirkulasjon
• Svangerskapet er en hyperterm tilstand
– Fosteret produserer varme, den må avgis via mor
• Placenta styrer produksjon av
svangerskapshormoner
– De molekylære mekanismene for mange
fysiologiske prosesser i svangerskapet er stort sett
ukjente, men hormonelle faktorer er viktige
–
HCG, hPL, østrogen, progesteron, prolactin, cortisol, cytokiner, adipokiner…
Lever:
• Forbruker glyserol og (i mindre grad) aminosyrer for å danne glukose som brukes av
fosteret
• Forbruker fett: danner ketoner som kan brukes av hjerne, muskler og foster
Fettvev:
• Frigjør fettsyrer til forbruk for lever og muskler
Fosteret:
• Forbruker aminosyrer, fett og halvparten av innkommende glukose for anabol vekst
• Siste halvparten av glukoseforbruket brukes til energibehov
Liu and Arany. Maternal cardiac metabolism in
pregnancy. Cardiovasc Res 2014
Vi skal gjennomgå forandringer i:
•
•
•
•
•
Hjerte- kar
Blod
Respirasjon
Nyrer
Gastrointestinaltraktus
Hjerte- kar
Blod
Respirasjon
Nyrer
Gastrointestinaltraktus
Svangerskapet reprogrammerer maternell metabolisme:
Maternell insulinresistens: begrenser maternell glukoseforbruk
→ shunting av det meste av glukose til fosteret
Stor uteroplacentær sirkulasjon
-essensielt i svangerskapsfysiologien
½ liter per minutt…
(Hytten F, Chamberlain G: Clinical Physiology in
Obstetrics. Boston, Blackwell Scientific Publications,
1980)
Normal placentering er essensielt i svangerskapsfysiologien for normal
uteroplacentær flow,
-inkluderer remodellering av uteroplacentære spiralkar (<uke 18)
Blod til uterus:
Ca 50 ml/min tidlig i svangerskapet
Ca 500 ml/min blod til uterus ved termin
• Hjertet løftes opp og roteres fremover:
• EKG-endringer (inverterte t-takker og STendringer kan forekomme)
• Arytmier hyppige (ekstrasystoler, sjeldnere
supraventrikulære tachycardier)
• Hjertets størrelse:
• Volum øker ca 10% (pga økt venøs fylning?)
• Remodellering: Venstre ventrikkelvegg øker i
tykkelse (ca 30% ved termin)
Manglende glatt
muskulatur i
normalt
remodellerte
spiralarterier:
Arteriovenøs
shunt og dermed
nedsatt perifer
motstand
Decidua= endometrium i graviditeten
«Der mor ser far» : uterine maternelle NK-celler
(KIR-reseptorer) «ser» invasive fetale trofoblaster
med paternelle gener (HLA-C)
Forandringer i puls og blodtrykk
Perifer motstand reduseres
Sirkulasjonen i placenta virker som en
arteriovenøs shunt og bidrar til
redusert perifer motstand
Blodtrykket (MAP) synker fra første trimester
80
70
60
50
40
30
20
10
0
pp
pp
Systolisk BT:
• Uendret eller faller litt
52
24
38
pp
Puls
Blodtrykk
Diastolisk BT:
• faller 5-10 mmHG utover i
2. trimester
• Termin: ikke-gravide
verdier
rs
Fø
Manglende glatt muskulatur i
normalt remodellerte
spiralarterier:
Arteriovenøs shunt og dermed
nedsatt perifer motstand
va
ng
e
12
32
24
8
16
rs
ka
p
85
84
83
82
81
80
79
78
77
76
75
Clapp AF III, Capeleas E: Am J Cardiol 1997; 80: 1469-73
Redusert perifer motstand: → BT-reduksjon,
BT-reduksjon motvirkes av:
↑minuttvolum
Aktivering av renin-angiotensin-systemet
Clapp AF III, Capeleas E: Am J Cardiol 1997; 80: 1469-73
Store hemodynamiske endringer i
svangerskapet
Hjertets slagvolum og
minuttvolum øker
Blodvolumet og
hjertefrekvensen øker
Cardiac output, heart rate, stroke volume, and blood volume:
- all increase between 5 and 8 weeks of gestation, peak by mid-pregnancy, and is
sustained until the end of pregnancy.
-are reversed by 6 months postpartum
Liu and Arany. Maternal cardiac metabolism in
pregnancy. Cardiovasc Res 2014
Graviditet:↑ Risiko for varicer og hemorrhoider
•
Stor uterus oØkt trykk i bekkenvener og v. femoralis
•
Økt vene-distensibilitet
Plasmavolum
Vi skal gjennomgå forandringer i:
•
•
•
•
•
•
Hjerte- kar
Blod
Respirasjon
Nyrer
Gastrointestinaltraktus
•
•
•
Normalt plasmavolum
hos ikke-gravid: 2600 ml
Øker med ca 50% (1200
–1500 ml) i løpet av
svangerskapet
Årsak: ukjent
Større økning ved flere
og større fostre
Hytten & Chamberlain 1980
Erytrocytter
•
•
•Plasmavolum øker mer enn
erytrocyttvolum i graviditeten:
Volum hos ikke-gravide:
1400 ml
Økning avhengig av
jerntilskudd
–
–
– Hemoglobin synker
– Hematokrit synker
Med jerntilskudd: 400 ml
Uten jerntilskudd: 240 ml
•Uforandret:
– MCHC (mean corpuscular hemoglobin
concentration)
– MCV (mean corpuscular volume)
Nedre normalgrense for Hb i
(normalt) svangerskap: 9-10g/dl
Hytten & Chamberlain 1980
Rasmusses S et al. Eur J of Obst and Gyn Reprod Biol 20115.
5024 haemoglobin measurements from a random sample of 552 pregnant
women in three Scandinavian locations, by week of pregnancy.
Lines denote the 5th, 10th, 50th, 90th, and 95th percentiles.
Andre endringer i blod
•
•
Hyperlipidemi (enda mer ved preeklampsi)
– HDL uforandret
– Total kolesterol og LDL øker 50%
– Triglycerider tredobles
Maternell insulinresistens:
– starter tidlig, reduseres med 80% sent i svangerskapet
– begrenser maternell glukoseforbruk (spesielt i musklene) → shunting av
det meste av glukose til fosteret
– Øker lipolyse i fettvevet→ gir fettsyrer som alternativ energikilde for mor og
glyserol som substrat til leveren for glukoneogenese
– enda mer insulinresistens ved preeklampsi/GDM..
•
Inflammatorisk tilstand (sammenlignet med ikke-graviditet, enda mer ved
preeklampsi)
– CRP normal eller litt økt
– Leukocytter stiger jevnt (10.2x109/l i 3. trimester)
•
Plasmaprotein (totalprotein og albumin)-konsentrasjonen ↓ (pga
plasmavolumøkning)
•
Trombocytter lett redusert mot termin (N: 150-290x109/l)
– Ca. 10 % har lett trombocytopeni (100- 150 x 109/l)
– Økt aktivering og økt nedbrytning (?)
• Kortere levetid (i hvert fall ved preeklampsi)
Hemostase
•
•
•
•
Fibrinogen øker betydelig i
svangerskapet
– Fordel for å forebygge blødning
ved placenta-separasjon
Andre koagulasjonsfaktorer øker
også:
– Faktor VIII og vWfaktor
Fibrinolytisk aktivitet nedsatt
– Pga fibrinolysehemmende
faktorer fra placenta?
– Som hos ikke-gravid ca 1 time
etter fødsel
Økt koagulabilitet og økt trykk fra
gravid uterus (økt trykk i
bekkenvener og v. femoralis):↑risiko
for venøs trombose
http://jama.jamanetwork.com/article.aspx?articleid=2297171
Respirasjon
Vi skal gjennomgå forandringer i:
•
•
•
•
•
Hjerte- kar
Blod
Respirasjon
Nyrer
Gastrointestinaltraktus
Diafragma ca 4 cm høyere
ved termin enn hos ikkegravide, men
interkostalvinkelen blir videre
Respirasjonsforandringer i svangerskapet
• Tidevolumet øker ca. 40 %
(på bekostning av det ekspiratoriske
reservevolumet)
• Skyldes økt utslag av diafragma (fra
4-5 til 5-7 cm utslag)
100%
• Respirasjonsfrekvens uendret
– Minuttvolumet øker (40%)
Lungefunksjon i
svangerskapet
1 maks inspirasjon
og maks ekspirasjon
3 vanlige
inspirasjoner
og ekspirasjoner:
en gravid puster
normalt inn, men
puster dypere ut
PEF = peak expiratory flow
(= maksimal ekspirasjonshastighet)
FVC = forced vital capacity
(= inspiratorisk reservevolum +
tidevolum + ekspiratorisk reservevolum)
FEV1 = forced expiratory volume in
1 second
+40%
FVC hos para > 0, dvs.
forandringene vedvarer etter
svangerskapet
100%
-20%
Residualvolumet reduseres med 20% i graviditet
fordi uterus presser diafragma oppover
Det funksjonelle lungevolumet er uendret
---- gravid
G Grindheim,K Toska,M-E Estensen,LA
Rosseland, BJOG 2011
___ ikke gravid
Ventilasjon
O2-forbruket øker i svangerskapet
O2-behovet øker 15 % pga
Foster, placenta, voksende uterus, økt hjerteog respirasjonsarbeid
Produksjonen av CO2 øker tilsvarende
•
•
•
•
•
•
•
Ventilasjonen mer økt enn nødvendig ift økt metabolisme
o fjerning av karbondioksid
o kronisk respiratorisk alkalose – renalt kompensert
Arteriell pCO2 5,3 kPa o 4,0 kPa
Bicarbonat nedsatt
pH uforandret
Skyldes antakelig: Respirasjonssenterets sensitivitet for CO2 n (pga
progesteron?)
• Hensikten med redusert maternell pCO2?
– Øke differansen mellom maternell og fetal pCO2 og dermed
diffusjonshastigheten for CO2 over placenta?
Vi skal gjennomgå forandringer i:
•
•
•
•
•
Hjerte- kar
Blod
Respirasjon
Nyrer
Gastrointestinaltraktus
Diameter av calyces og
ureteres øker i
svangerskapet
Kan vedvare 3-4 mnd
postpartum
Årsak? Mekanisk trykk i
graviditet/økt venepleksus
rundt indre genitalia?
Større diameter på høyre enn på venstre
side
•
Vena ovarica-syndrom: høyresidige
ureterstenliknende smerter pga
utvidelse av ureter i graviditet
Peake et al. Radiology 1983; 146:167-70
Nyrefysiologi
• Ukjent årsak til endringene:
– Blodgjennomstrømning n 30 – 50 %
– Glomerulusfiltrasjon øker
– Tilbakeresorbsjon øker
• Glukosuri – skyldes økt glomerulusfiltrasjon
(reabsorbsjonen øker ikke alltid tilsvarende)
Væskebalanse
• 6-8 liter vann retineres ila svangerskapet
– Økt plasmavolum
– Ekstracellulær væske
• Mange gravide: økende ødemer ila dagen, skilles ut om
natten/hvile
• Moderate svangerskapsødemer er normalt
– Men rask økning KAN sees ved alvorlig preeklampsi pga dysfunksjonelt
endotel
• Utskillelse av vannløselige vitaminer og
aminosyrer øker
– Økt behov for inntak i svangerskapet
Vi skal gjennomgå forandringer i:
•
•
•
•
•
Hjerte- kar
Blod
Respirasjon
Nyrer
Gastrointestinaltraktus
Gastrointestinaltraktus
• Nedsatt tonus og motilitet i glatt muskulatur
– Forlenget tømningstid av ventrikkel
• Spesielt under fødsel
– Obs brekninger/aspirasjon ventrikkelinnhold ved narkose
– Obstipasjon pga nedsatt kolonmotilitet
– Bidrar til svangerskapskvalmen i 1. trimester?
Normal vektøkning i svangerskapet: store variasjoner
• Svangerskapsprodukter:
• Foster
• Placenta
• Fostervann
• Fettdepot øker (ca 2 kg ved
god næring-tilgang)
• Væskeretensjon (blodvolum
og annen ekstracellulær
væske)
• Uterus og mamma vokser
http://www.nap.edu/read/12584/chapter/5
Pitkin, 1976. Nutritional support in obstetrics and
gynecology. Clinical Obstetrics and Gynecology
19(3): 489-513.
Oppsummert:
•
•
Metabolisme: øker 15%
Hjerte- kar:
–
–
–
CO øker 30-40%
Hjertefrekvens og slagvolum øker
Vaskulær motstand reduseres (økt
uteroplacentær flow)
•
Blod:
•
Respirasjon
–
–
–
•
Ventilasjonen øker 50%
O2-forbruk øker 20%
Nyrer
–
–
•
Volum øker 30%
GFR øker 50%
Tubulær reabsorpsjon øker 50%
Gastrointestinaltraktus
–
Tregt
Placenta: the key to pregnancy success (og nøkkel til svangerskapsendringer)
Svangerskap
Ernæring og ernærings tilskudd i
svangerskapet
Maternell
Føtal
Ernæring
Ernæring
Janette Khoury MD, PhD
Spesialist i Kvinnesykdommer og Fødselshjelp
Post Doc Universitetet i Oslo
Privatpraktiserendespesialist Brynmedisinske Senter
E-mail: [email protected]
Januar 2016
Umbilical artery
Carrying the fetal blood to the placenta
for exchange of gases and nutrients
Optimal forhold
Sunt og balansert
kosthold
for
føtal utvikling og tilvekst
Metabolske tilpassninger i svangerskapet
Metabolske tilpassninger i svangerskapet
Maternell hyperkolesterolemi
Maternell hypertriglyceridemi
Plasma
LDL
3
Cholesterol
(mmol/l)
HDL
mmol/L
6
7,5
7
6,5
6
5,5
5
4,5
4
3,5
3
2,5
2
1,5
1
0,5
Trigly
wk 8
wk 20
wk 30
wk 38
VLDL
nonpregnant
8
14
20
28
36
wk pregnancy
Lactation
Pregnancy weeks
Modified after Fåhraeus, MD et al. Obstetrics & Gynecology 1985; 66: 468.
Avgjørende faktorer som påvirker
føtal ernæring og føtal tilvekst
Endringer i spiral arterier
Maternal side
Gjennomblødning i
The placenta
uteroplacental årer
kan øke med 10%
ƒ Uteroplacental gjennomblødning
kontrol mekanismer i
(placentær svikt)
ƒ Overføring av næringsstoffer
over placenta
åreveggen som styrer
utvidelse eller konstriksjon
Preeclampsia
Normal
Fetal side
av blodårene.
ƒ Morens endokrine og
metabolsk faktorer
(f.eks maternal hypercholesterolemia)
(f.eks maternal hyperinsulinemia)
uavhengig av maternal
Secretary fase
ƒ Mors ernærings tilstand,
metabolsk kapasitet, og daglig inntak
ƒ Fosterets evne til å nyttig seg
næringsstoffene (medfødte misdannelse,
kromosomfeil)
Tore Henriksen, Acta Pædiatrica Suppl 1999; Godfrey et al Am J Clin
Nutr,2000; Barker DJP Theriogenology 2000,
Føtal tilvekst versus fødselsvekt
Growth
Normal
Flere føtal tilvekst mønstre men
samme fødselsvekt
Large
restricted
A Late growth restriction
B Early growth restriction
C Normal growth
D Late growth restriction
followed by catch up growth
Harding, International Journal of Epidemiology 2001; 30 (1): 15-23.
Trenger ikke å spise for to
300-400 kcal ekstra fra 2 trimester
Kost veiledning
Nøvendig at det startes før
svangerkapet
- En ekstra liten mellom måltid (300-400 kcal)
• 1 tykk skive grovt brød med mager pålegg + grønnsak
• 1 glass skummet melk
• 1 eple
Vekt økning i svangerskapet
Kost råd i svangerskapet
Amerikanske anbefalinger
Institute of Medicine (IOM) 2009:
Balansert sun kost
BMI kg/m2
Før konsepsjon
Anbefalt vektøkning (kg)
pr uke 2dre og
Totalt /
3dje trimester
Lav < 18,5
12,5-18,0 /
≥ 0,5
Normal 18,5-24.9
11,5-16,0/
0,4
Høy 25,0-29.9
7,0-11,5 /
≤ 0,3
Fedme > 30,0
5-9 /
≤ 0,2
National academies press (US); 2009
• Fisk 2 ganger i uken. Gjerne fet fisk.
• Skummet melk, ekstra lett melk, lett melk eller
lett yoghurt
• Lett margarin på brød. Flytende margarin eller
vegetabilsk olje til matlaging.
• Magert kjøtt, kylling, egg, bønner, linser / erter.
• Grøvt brød, poteter, ris, pasta. Gjerne
fullkornalternativer.
• Frukt og grønnsaker.
• Kutt ned på inntaket av sukker.
Kost råd i svangerskapet
Kosttilskudd
Balansert sun kost
• Kosttilskudd kan ikke erstatte det mangfoldet av
stoffer som et sunt og variert kosthold gir. Tar
kvinnen kosttilkudd, kan hun få i seg for mye av
enkelte næringsstoffer.
Total fett
30 E%
Mettet fet
Protein
Karboydrater
10 E%
15 E%
55 E%
Fisk 2 ganger i uken, frukt og grønnsaker daglig
(3 forskjellige grønnsaker og 2 forskjellige frukt)
Spesielle behov i svangerskapet
• Høyere energi fra midten av svangerskapet.
•Vitamin og mineral tilskudd?
• Kvinner med spesial behov (melk intolerance, vegetarianer,
malabsorption, anorexi, fedme)
Folate
• Ønske den gravide likevel å ta kosttilskudd, er
det viktig å følge doseringen som er angitt på
kosttilskuddet og ikke ta flere ulike typer
kosttilskudd som inneholder de samme
vitaminene og mineralene.
Generelle spesial behov
• Folate
• Long chain essential fatty acids (omega 3)
• Vitamin D
• Calcium
• Jern
Folate Meabolism
a donor of methyl group
Folate - 400µg/d (under planlegging og opptil 12 uker)
- 200µg/d (resten av svangerskapet) ?
Source: Cummings AM, Kavlock RJ. Crit Rev Toxicol 2004;34:461-85.
Drop in prevalence of spina bifida and
anencephaly after food fortification
with folic acid
Maternal Vitamin B12 status
og risiko for NTD
Befolkning
6,0
Spina bifida
5,0
Prevalence (per 10,000)
Anencephaly
Irland, high NTD prevalens uten folat tilsettinger.
4,0
Resultater:
3,0
Mødre i lavere B12 kvartiler sammenliknet med
mødre i høyeste kvartiler, hadde 2 to 3 økt odds
for å bære en foster med NTD
2,0
1,0
Pre-fortification
Optional Fortification
Mandatory Fortification
0,0
1995
1996
1997
198
1999
2000
2001
Molloy et al . Pediatrics 2008
Teratology 2002; 66:33-39. Updated 6/2004.
Long chain essential fatty acids
Kan omega-3 forebygge
preterm fødsel
(omega 3)
Fiske olje inntak - Få RCT
Daglig behovet av omega-3 (0,7-1,2g)
dekkes av:
Tran
5ml/d (barne skje)
eller (2 kapsler)
Vitamin D
7.5 – 10 µg/d
f.eks. Bruk en av følgende:
-2 kapsler møllers dobbel
- 5ml Tran
- 1 tablett a’10μg D-vitamin
- 10ml/d ‘Sanasol’
- 3 RCT inkludert i en metaanalyse hvor 10 studier var eksludert
da de ikke fylte kriteriene.
- Disse 3 RCT påvist 20-30% reduksjon i forekomst av prematur
fødsel. Dosen som ble brukt var 2,7g/d.
(Salvig JD et al. AOGS; 2011)
Kolesterol reduserende kosthold i regi av en balansert sun
kosthold (fetfisk x2 i uken) kan være lovende i risiko reduksjon
av prematur fødsel men trenger mer forskning
(KHOURY et al. AOGS; 2005)
(CARRDIP STUDEIN).
Calcium
• 500 – 1000 mg /d til de med lavt inntak
e.g. milk intolerance, vegetarians if they do not drink soya milk
•
Anbefalt daglig inntak (900 mg)
- 3 glass skummet milk
- 2 skiver ost
- 1 porsjon yoghurt naturell
• Vegetabilske matvarer rik in Ca++ :
Mandler , Tørket fiken, Sesam frø, Grønn kål, Spinat.
Iron
• Daglig behov i kost 12-18mg/d (opptak 3-8g/d).
_Jern absorbsjon øker i andre og tredje trimester
Viktig å holde unna
Grunnet bacteria eller dioksiner og PCB
• Fisk lever
• Upastørisert melk og melkeprodukter
• Rå fisk og kjøtt produkter
• ’Innmat’ fra crabbe
• Hval kjøtt og stor tuna og andre stor fisk.
Iron
Norske anbefalinger fra 2005
‰ Rutinemessig jerntilskudd anbefales ikke.
Tilskudd anbefales når:
• WHO råd hos kvinner i fertil alder
60 mg /d som tilskudd fra sv. Uke 20 hvis
- Serum ferritin < 20µg/l eller Hgb < 11g/100ml
WHO/CDC Technical consultation at the population level 2005
- Tilskudd i form av Fe2+:
Ferromax 65mg x1/Hemofer 27mg x2.
Drikke
‰ Hgb < 11g/100ml ved første kontroll og i uke 28.
‰ S-Ferritin < 20 Pg/l, jerntilskudd fra sv uke 20.
Anbefales målt før sv. uke 15.
Etter sv. uke 15, S-Ferritin ikke god indikator. Anbefales
da å måle S-Transferrinreseptor i tillegg.
Viktig å holde unna
Vann er den beste drikke
Grunnet bacteria eller dioksiner og PCB
• Kaffe 1-2 kopper pr dag
• Te 3 – 4 kopper pr dag
• Akohol avholdene
• Minst mulig ’brus’
• Fisk lever
• Upastørisert melk og melkeprodukter
• Rå fisk og kjøtt produkter
• ’Innmat’ fra crabbe
• Hval kjøtt og stor tuna og andre stor fisk.
Sammendrag
Grupper som trenger kost veiledning
• BMI < 19-20 or BMI > 30
• Kvinner som har gjennomgått fedme operasjon.
• Røykere
• Tenår svangerskap
• Lav socioeconomisk status
• Innvandrere
• Diabetes, anorexi, GI problemer
• Tidligere spinabifida (4 mg folate i første trimester)
• Tidligere svangerskaps komplikasjoner
ƒ
Kostveiledning bør helst starte før svangerskapet.
ƒ
Følge generelle råd for sunt og balansert kosthold.
ƒ
Kvinner med BMI > 30 eller < 19 ved start av svangerskapet, og kvinner
med lav vekt økning under svangerskapet bør få kostveiledning.
ƒ
Vitamin and mineral tilskudd ikke nødvendig med unntak av:
- Folat 400µg under planlegging og ut første trimester.
- D-vitamin for alle spesielt vinter halv året.
- Folate 200µg resten av svangerskapet, og Calcium tilskudd for de med
marginal og lav inntak.
ƒ
Jern tilskudd ved indikasjon.
ƒ
Kolesterol reduserende kosthold i regi av en balansert sunt kosthold
kan være lovende i risiko reduksjon av fortidlig fødsel men trenger mer
forskning.
Brosjyren ernæring i
svangerskapet
THE CARRDIP STUDY
www.helsedirektoratet.no
Cardiovascular risk
reduction diet in pregnancy
CARRDIP studien
THE CARRDIP STUDY
Kost Intervensjons gruppen
1.
2.
3.
Spise fisk x 2 i uken spesielt fet fisk, rent kjøtt og fjærkre,
olivenolje, rapsolje, frukt, grønnsaker,nøtter, belgfrukter, lett
melk og magre oster
Janette Khoury, Tore Henriksen, Bjørn Chrisophersen, Serena Tonstad. Effect
of a cholesterol lowering diet on maternal, cord, neonatal lipids and pregnancy
outcome. A randomized clinical trial. American Journal of Obstetrics and
Gynecology 2005;193:1292-30.
Janette Khoury, Tore Henriksen, Ingebjørg Seljeflot, Lars Mørkrid, Kathrine Frey
Frøslie, Serena Tonstad. Effect of an antiatherogenic diet during pregnancy on
markers of maternal and fetal endothelial activation and inflammation: the
CARRDIP study. British Journal of Obstetrics and Gynecology Br J Obstet
Gynaecol 2007;114:279 – 288.
Janette Khoury, Guttorm Haugen, Serena Tonstad , Kathrine Frey Frøslie, Tore
Henriksen Effect of a cholesterol-lowering diet during pregnancy on maternal
and fetal Doppler velocimetry: The CARRDIP study. American Journal of
Obstetrics and Gynecology 2007 Jun;196(6):549.e 1-7.
SH direktoratet link
for brosjyren ernæring i
svangerskapet
https://helsedirektoratet.no/
publikasjoner/gravid
Seminars in Fetal & Neonatal Medicine (2005) 10, 493e503
www.elsevierhealth.com/journals/siny
Physiology of the fetal circulation
Torvid Kiserud a,b,*
a
Department of Obstetrics and Gynaecology, Institute of Clinical Medicine, University of Bergen, Bergen,
Norway
b
Fetal Medicine Unit, Department of Obstetrics and Gynaecology, Haukeland University Hospital,
Bergen, Norway
KEYWORDS
Circulation;
Blood flow;
Fetus;
Placenta;
Ductus venosus;
Ductus arteriosus;
Foramen ovale;
Liver
Summary Our understanding of fetal circulatory physiology is based on experimental animal data, and this continues to be an important source of new insight
into developmental mechanisms. A growing number of human studies have investigated the human physiology, with results that are similar but not identical to those
from animal studies. It is time to appreciate these differences and base more of our
clinical approach on human physiology. Accordingly, the present review focuses on
distributional patterns and adaptational mechanisms that were mainly discovered
by human studies. These include cardiac output, pulmonary and placental circulation, fetal brain and liver, venous return to the heart, and the fetal shunts (ductus
venosus, foramen ovale and ductus arteriosus). Placental compromise induces a set
of adaptational and compensational mechanisms reflecting the plasticity of the
developing circulation, with both short- and long-term implications. Some of these
aspects have become part of the clinical physiology of today with consequences for
surveillance and treatment.
ª 2005 Elsevier Ltd. All rights reserved.
Introduction
Many of the mechanisms described in animal
experiments also occur in the human fetus, but
with differences. The reasons for variation are
many, e.g. a sheep fetus has a different anatomy
compared with a human fetus, with a longer
intrathoracic inferior vena cava (IVC), a smaller
* Department of Obstetrics and Gynaecology, Haukeland
University Hospital, N-5021 Bergen, Norway. Tel.: C47
55974200; fax: C47 55974968.
E-mail address: [email protected]
brain, the fetal liver is positioned differently, two
umbilical veins, a higher temperature, a lower
Haemoglobin (Hgb), a higher growth rate and
a shorter pregnancy. Ultrasound in obstetrics has
been used increasingly to provide physiological
data from human fetuses, and this is reflected in
the present review.
Blood volume
The blood volume in the human fetus is estimated to
be 10e12% of the body weight, compared with 7e8%
1744-165X/$ - see front matter ª 2005 Elsevier Ltd. All rights reserved.
doi:10.1016/j.siny.2005.08.007
494
in adults.1 The main reason for this difference is the
large pool of blood contained within the placenta;
a volume that reduces as gestation progresses.
The calculated blood volume of 90e105 ml/kg in
fetuses undergoing blood transfusion during the
second half of pregnancy2 is probably an underestimate. Other studies have indicated a volume
of 110e115 ml/kg, which is more in line with experimental sheep studies.3 The estimated volume
of 80 ml/kg contained within the fetal body is
marginally more than that in adults. Compared
with adults, the fetus is capable of much faster
regulation and restoration of the blood volume
due to high diffusion rates between fetal
compartments.1
Arterial and venous blood pressure
The mean arterial pressure in human fetuses was
measured to be 15 mmHg during cordocentesis at
gestational weeks 19e21.4 Intra-uterine recording
of the intraventricular pressure in the human fetus
suggests that the systemic systolic pressure increases from 15e20 mmHg at 16 weeks to 30e
40 mmHg at 28 weeks.5 There was no obvious
difference between the left and right ventricles.
This increase was also seen for diastolic pressure,
which was %5 mmHg at 16e18 weeks and 5e
15 mmHg at 19e26 weeks.
Umbilical venous pressure, recorded during
cordocentesis and corrected for amniotic pressure,
increased from 4.5 mmHg at 18 weeks to 6 mmHg
at term.6
Cardiac performance
Structural details of the heart are organized during
the embryonic period but are dependent on the
physical environment, including blood flow, in
order to develop normally. The myocardium grows
by cell division until birth, and growth beyond
birth is due to cell enlargement. The density of
myofibrils increases particularly in early pregnancy
and the contractility continues to improve during
the second half of pregnancy.7 The two ventricles
perform differently in pressure/volume curves
and when tested with intact peripheral vasculature.8 The fetal heart has limited capacity to
increase stroke volume by increasing diastolic filling pressure, the right ventricle even less than
the left, as they are already operating at the top
of their function curves. The FrankeStarling mechanism does operate in the fetal heart, which is
T. Kiserud
apparent during arrhythmias.9 Adrenergic drive
also shifts the function curve to increase stroke
volume. However, increased heart rate may be
the single most prominent means of increasing cardiac output in the fetus.
The two ventricles pump in parallel (Fig. 1) and
the pressure difference between them is minimal
compared with postnatal life.5 However, experimental studies show some variation in pressure
and velocity waves between the two sides, ascribed to the difference in compliance of the great
arteries and downstream impedance (upper body
vs lower body and placenta).10 Some of the ‘stiffness’ of the fetal myocardium is attributed to
the constraint of the pericardium, lungs and chest
wall,11 all of which have low compliance before air
is introduced. However, with the shunts in operation and a metabolism capable of extracting oxygen at low saturation levels, the fetal heart
appears to be a very flexible, responsive and adaptive structure.
Cardiac output and distribution
The fetal systemic circulation is fed from the left
and right ventricles in parallel. The left ventricle is
predominantly dedicated to the coronary circulation and upper body, while the right ventricle is
the main distributor to the lower part of the body,
the placenta and the lungs. When using outerinner diameter measurements of the vessels, the
combined cardiac output (CCO) is reported to be
210 ml/min at mid-gestation and 1900 ml/min
at 38 weeks12 (Table 1). When using inner diameters, these numbers are lower.13 The right ventricular output is slightly larger than that of the left
ventricle, and pulmonary flow in the human fetus
is larger (mean 13e25%) than in the classical fetal
lamb studies (%10%). Interestingly, a developmental transition in fetal haemodynamics seems to occur at 28e32 weeks when the pulmonary blood
flow reaches a maximum with a simultaneous
change in oxygen sensitivity in the pulmonary vasculature.12,14 Another study found that less blood
was distributed to the fetal lungs (11%),13 which
is more in line with previous experimental studies.
The three shunts (ductus venosus, ductus arteriosus and foramen ovale) are essential distributional arrangements that make the fetal
circulation a flexible and adaptive system for
intra-uterine life. A classical concept describes
the pathway of oxygenated blood as the via
sinistra (Fig. 1) leaving the umbilical vein through
the ductus venosus to reach the foramen ovale,
left ventricle and aorta, thus feeding the coronary
Physiology of the fetal circulation
495
Figure 1 Pathways of the fetal heart and representative oxygen saturation values (in brackets). The via sinistra
(red) directs well-oxygenated blood from the umbilical vein (UV) through the ductus venosus (DV) (or left half of
the liver) across the inferior vena cava (IVC), through the foramen ovale (FO), left atrium (LA) and ventricle (LV)
and up the ascending aorta (AO) to reach the descending AO through the isthmus aortae. De-oxygenated blood
from the superior vena cava (SVC) and IVC forms the via dextra (blue) through the right atrium (RA) and ventricle
(RV), pulmonary trunk (PA) and ductus arteriosus (DA). CCA, common carotid arteries; FOV, foramen ovale valve;
LHV, left hepatic vein; LP, left portal branch; MHV, medial hepatic vein; MP, portal main stem; PV, pulmonary
vein, RHV, right hepatic vein; RP, right portal branch. Copied and modified with permission from ref.16
and cerebral circuits. Conversely, a via dextra directs de-oxygenated blood from the caval veins
through the tricuspid valve, pulmonary trunk and
ductus arteriosus to reach the descending aorta,
largely bypassing the pulmonary circuit.
Oxygen saturation gives a picture of distribution
and blending of flows in the central fetal circulation (Fig. 1). The lowest saturation is found in the
abdominal IVC, and the highest saturation is found
in the umbilical vein.10 Interestingly, the
difference between the left and right ventricles
is only 10%, and this increases to 12% during hypoxaemia. The small difference between the left and
right ventricles is due to the abundant volume of
oxygenated blood presented to the foramen ovale.
In addition to the ductus venosus blood flow, the
umbilical blood passing through the liver has had
a modest reduction in saturation and represents
another sizeable volume of oxygenated blood flowing in much the same direction as the ductus
496
T. Kiserud
Table 1 Combined cardiac output and distribution
in human fetuses during the second half of pregnancy
according to Rasanen et al.12
% of combined cardiac output at
gestational age
20 weeks 30 weeks 38 weeks
Combined cardiac
output
Left ventricle
Right ventricle
Foramen ovale
Lungs
Ductus arteriosus
210 (ml/
min)
47
53
34
13
40
960 (ml/
min)
43
57
18
25
32
1900 (ml/
min)
40
60
19
21
39
venosus towards the foramen ovale. In addition to
some blending, the abundance of oxygenated
blood will cause a spillover to the right side when
reaching the foramen ovale with its crista dividens
(limbus) (Fig. 2).
Ductus venosus and liver circulation
In the human fetus, the ductus venosus is a slender
trumpet-like shunt connecting the intra-abdominal
umbilical vein to the IVC at its inlet to the heart.
The inlet of the ductus venosus, the isthmus, is the
restrictive area with a mean diameter of 0.5 mm at
mid-gestation and hardly exceeds 2 mm for the
rest of a normal pregnancy.15,16 The umbilical venous pressure ranges from 2 to 9 mmHg6 (the portocaval pressure gradient), and causes the blood
to accelerate from a mean of 10e22 cm/s in the
umbilical vein to 60e85 cm/s as it enters the ductus venosus and flows towards the IVC and foramen
ovale.17,18 The blood flow with the highest oxygenation, coming from the ductus venosus, also has
the highest kinetic energy in the IVC and predominantly presses open the foramen ovale valve to
enter the left atrium, i.e. the ‘preferential
streaming’ described in animal studies.19
While 30% of the umbilical blood is shunted
through the ductus venosus at mid-gestation,
this fraction is reduced to 20% at 30 weeks and
remains so for the rest of the pregnancy, but with
wide variations (Fig. 3).16 These results are similar
to those of another study,20 but are at variance
with experimental animal studies, admittedly
using a different technique, which showed that approximately 50% was shunted through the ductus
venosus.19,21 The redistributional mechanisms of
increased shunting during hypoxaemia described
in animal experiments also seem to operate in
the human fetus.22,23
Figure 2 The foramen ovale acts as a flow distributor
of the inferior venous inlet. (a) Ultrasound scan shows
the inferior vena cava (IVC) and left and right atria
(LA, RA). The atrial septum (AS) with its crista dividens
(postnatal: limbus) faces the inlet of the IVC to divide
the ascending column of blood. The terminal portion
of the IVC expands, more to the left side, to receive
blood from the liver and ductus venosus (DV). The high
velocity, its position to the left and steep direction (b)
makes the DV blood preferentially press open the foramen ovale valve (FOV) to enter the LA. IVC blood directed more anteriorly arrives predominantly in the RA.
Increased pressure in LA or a premature apposition of
FOV to the AS would divert more blood to the right. Reproduced with permission from ref.36
The ductus venosus is under tonic adrenergic
control, and distends under the influence of nitroxide and prostaglandins.24,25 The most extensive
dilatation is seen during hypoxaemia, leading to
Physiology of the fetal circulation
Figure 3 The fraction of umbilical venous return
shunted through the ductus venosus in low-risk pregnancies is 30% at mid-gestation but approximately 20% at
30e40 weeks, signifying the developmental importance
of the fetal liver receiving 70e80% of the umbilical
blood. Reproduced with permission from ref.16
a 60% increase of the diameter in fetal sheep.25
However, the changes in diameter are not restricted to the isthmus but also include the entire
length of the vessel, which has a far greater
impact on resistance.25,26 The shunt obliterates
within 1e3 weeks of birth in term infants, although
this takes longer in premature births and in cases
with persistent pulmonary hypertension or cardiac
malformation.27e29 In contrast to the ductus arteriosus where increased oxygen tension triggers
the closure, no trigger has been found for the ductus venosus.24
Equally important to the active regulatory
mechanism is the passive regulation based on fluid
dynamics, i.e. viscosity and pressure.30 Blood velocity in the ductus venosus is high and has Newtonian properties with low viscosity (similar to
water). In contrast, liver tissue represents a huge
capillary cross-section with a low blood velocity.
At low velocities, the blood is non-Newtonian
with an accordingly high viscosity (and resistance)
and a closing pressure of 1e4 mmHg. It follows
that an increase in haematocrit leads to increased
viscous resistance in the low-velocity venous liver
flow and has little effect on the high-velocity
flow in the ductus venosus. Thus, the change in
haematocrit alone leads to a shift of umbilical venous flow from the liver to the ductus venosus.
497
Along the same lines, variation in the umbilical
venous pressure affects the two pathways differently.30 A reduction in venous pressure reduces
liver perfusion more than ductus venosus flow, as
a further reduction in an already low velocity in
the large cross-section of the portal vasculature
implies a considerable increase in viscous resistance. The result is a higher degree of shunting.
In addition to these fluid dynamic determinants,
the neural and endocrine regulation of the hepatic
vascular bed also play a role.31 The portal vasculature shows a more pronounced constricting response to adrenergic stimulation compared with
the ductus venosus.32 It all combines to make a distribution system that is extremely sensitive to both
active and passive regulation, which is in line with
the substantial normal variation of shunting seen
in human fetuses.16,33
The physiological role of the ductus venosus is
not well understood. The shunting seems more
prominent in early pregnancy than after 30 weeks
of gestation. The low degree of shunting through
the ductus venosus during the last 8e10 weeks of
pregnancy implies that approximately 80% of the
umbilical blood perfuses the liver, signifying a very
high developmental priority of the umbilical liver
perfusion compared with the ductus venosus.16
However, during hypoxic challenges, the priority
seems to be different. Fetuses maintain a higher
degree of ductus venosus shunting, probably as
a redistributional adaptation to hypoxic pressure,
ensuring oxygenation of the heart and brain.21
The cost for responding to such needs could be
permanently altered liver development.34
It should be borne in mind that oxygen extraction in the liver is rather modest (10e15% reduction in oxygen saturation),35 which means that
blood coming from the median and left hepatic
vein are important contributors of oxygenated
blood. Actually, the position and direction of the
left hepatic venous blood under the Eustachian
valve (IVC valve) favour this blood to be delivered
at the foramen ovale.36
Although agenesis of the ductus venosus has
been linked to abnormalities and fetal demise,37
agenesis is also found in fetuses that have exhibited normal growth.16 Experimental obliteration
of the vessel seems to have little haemodynamic
effect,38 but causes an increase in insulin-like
growth factor 2 and increases the growth of fetal
organs.39 Recent studies have indicated that the
fetal umbilical flow to the liver towards the end
of pregnancy is influenced by the maternal nutritional state and diet.40 Umbilical venous flow constitutes 75% of the venous supply to the liver, with
the remaining 25% coming from the main portal
498
stem.41 In human fetuses, the arterial supply to the
liver is not known but it seems to have a more
prominent role during compromise.42
Doppler examination of the ductus venosus is
increasingly used to identify hypoxaemia, acidosis,
cardiac decompensation and placental compromise, and is a promising tool for timing the
delivery of critically ill fetuses.43,44 Increased pulsatility, mainly caused by the augmented atrial
contraction wave, signifies increased atrial contraction due to adrenergic drive, or increased venous filling pressure, or both.
In early pregnancy, the augmented a-wave in
the ductus venosus is associated with an increased
risk of chromosomal aberration and has been
suggested as a secondary screening test.45,46
Foramen ovale
A defect in the atrial septum is commonly associated with left-right or right-left shunting in postnatal life. It is conceivable that this concept is
carried over to describe the function of the
foramen ovale in the fetus,47 but this is not a fair
representation of the actual haemodynamics.
Rather, the inferior venous inlet to the heart
should be viewed as a column of blood that ascends between the two atria from below.36,48
This column hits the interatrial ridge, the crista
dividens, and is divided into a left and right arm
(Fig. 2). The left arm fills the ‘windsock’, formed
between the foramen ovale valve and the atrial
septum, to enter the left atrium. The right arm is
directed towards the tricuspid valve and joins
the flow from the superior vena cava and coronary
sinus to form the via dextra.
This is an equilibrium easily influenced by
changes in pressure on the two sides. Increased
T. Kiserud
resistance and pressure of the left side is instantaneously reflected in increased diversion of
blood to the right side. In contrast to the hypertrophy of the left ventricle seen in aortic stenosis
in adults, fetal stenosis commonly leads to a shift
of blood volume from left to right at the level of
the foramen ovale, with corresponding development of left-sided hypoplasia and compensatory
growth of the right ventricle.
The developing ventricle responds to the demands of the afterload and is stimulated by the
blood volume of the preload. However, for the left
side of the heart, the foramen ovale is an important limiting factor, particularly in cases of a maldeveloped foramen or a premature closure.49
Under physiological conditions, it is not the ovalshaped hole of the septum that constitutes the restricting area for the flow to the left atrium, but
the horizontal area between the foramen ovale
valve and the atrial septum above the foramen
ovale.50 Interestingly, the growth of this area is
somehow blunted after 28e30 weeks of gestation
compared with the cross-section of the IVC. This
effect coincides with changes in fetal lung perfusion12 and ductus venosus shunting,16 and may signify a transition into a more mature circulatory
physiology.
Ductus arteriosus and pulmonary
circulation
The ductus arteriosus constitutes a wide muscular
vessel connecting the pulmonary arterial trunk to
the descending aorta (Fig. 4).51 During the second
trimester, the velocity in the ductus arteriosus increases more than that in the pulmonary trunk, reflecting the development of the wind-kessel
function of the pulmonary trunk.52 During the
Figure 4 (a) The ductus arteriosus (arrow) is a sizeable connection between the pulmonary trunk (PA) and the aorta
(AO) in fetal rats. (b) Indomethacin induces severe constriction. Reproduced with permission from ref.51
Physiology of the fetal circulation
second half of pregnancy, 40% or less of the CCO is
directed through the ductus arteriosus12,13 (Table 1).
The lungs receive 13% of the CCO at mid-gestation
and 20e25% after 30 weeks,12 which is more than
that reported in fetal sheep experiments10 and
a more recent human study.13 Normally, the shunt
closes 2 days after birth,53 but a patent duct is
a common clinical problem. An increase in oxygen
tension is regarded as the main trigger for its closure.24 The vessel is under the general influence
of circulating substances, particularly prostaglandin E2, which is crucial in maintaining patency.54
Sensitivity to prostaglandin antagonists is at its
highest in the third trimester and is enhanced by
glucocorticoids and fetal stress.55 Nitric oxide has
a relaxing effect prior to the third trimester. The
increased reactivity of the ductus arteriosus in
the third trimester makes it vulnerable to prostaglandin synthase inhibitors, such as indomethacin,
which may cause severe and longlasting
constriction.55,56
The ductus arteriosus bypasses the pulmonary
circuit, but the distribution between these two
pathways depends heavily on the impedance of the
pulmonary vasculature, which is under the control
of prostaglandin I2 and modified by a series of
substances.24 In an elegant study, Rasanen et al.
showed how reactivity in the pulmonary vascular
bed increased in the third trimester.14 While
fetuses at gestational age 20e26 weeks showed
no changes during maternal hyperoxygenation, fetuses at 31e36 weeks had lower impedance in the
pulmonary arteries assessed by the pulsatility index, and increased pulmonary blood flow. Correspondingly, the blood flow in the ductus
arteriosus was reduced.
Brain circulation
Differences in circulation physiology between animal experiments and human fetuses are likely to
be greatest when concerning the brain, as the
human brain is relatively larger than in other
species. In a study of human previable fetuses
weighing 12e272 g (probably corresponding to 10e
20 weeks of gestation), it was found that the brain
received approximately 15% of the systemic venous return (equal to the CCO less the pulmonary
circuit).33 The proportion directed to the brain increased with low arterial pH, increased pCO2 and
reduced placental perfusion. A study of the primate Macaca mulatta at an advanced stage of gestation found that 16% of the CCO was distributed
to the brain, and this fraction increased to 31%
during hypoxic challenge.21 Both of these studies
499
reflect redistributional preferences to the brain
during hypoxaemia and acidosis. Clinical obstetrics
has taken advantage of such ‘brain-sparing’ mechanisms, and uses the increased diastolic blood velocity recorded in the middle cerebral artery as
a marker of compensatory redistribution of blood
to the brain.57
Fetoplacental circulation
In the fetal sheep, 45% of the CCO is directed to the
umbilical arteries and placenta.58 This percentage
is less in exteriorized human fetuses, but it increases from 17% at 10 weeks to 33% at 20 weeks
of gestation.33 These results overestimate the placental fraction as the CCO calculation was based on
systemic venous return, not including the pulmonary venous return. Secondly, the measurements
were not performed under strict physiological conditions. Doppler studies of low-risk pregnancies
have found similar results; one-third of the fetal
CCO is directed to the placenta at 20e32 weeks
of gestation,59,60 but this decreases to approximately one-fifth beyond 32 weeks of gestation.60
The introduction of Doppler ultrasound made it
possible to assess umbilical venous blood flow61 in
the human fetus in utero. Recent longitudinal observations in low-risk pregnancies have found
that the umbilical blood flow increases from
a mean of 36 ml/min at 20 weeks to 265 ml/min
at 40 weeks of gestation.62 Umbilical flow normalized for fetal weight is at its highest (117 ml/min/
kg) at 25 weeks and at its lowest at 41 weeks
(63 ml/min/kg) of gestation. These results are in
accordance with earlier studies applying thermodilution at birth.63 The fact that human umbilical
flow is considerably lower than that in the fetal
sheep is not disconcerting as fetal sheep have
a higher growth rate, a higher temperature and
a lower Hgb.
Resistance to flow is mainly determined by
the peripheral vascular bed of the placenta. This
vasculature has no neural regulation and catecholamines have little effect on the vasculature.
Endothelin and prostanoid have a constricting
effect64 and nitric oxide has a vasodilatory effect,65
but the exact role of humoral regulation is not fully
understood.66 Placental blood flow has been found
to be fairly stable and chiefly determined by arterial blood pressure.10 The substantial increase in
the vascular cross-section during late gestation accounts for a reduction in impedance and the corresponding fall in umbilical artery pulsatility seen in
longitudinal studies.67 Placental vasculature is believed to account for 55% of the umbilical
500
resistance.68 The waveform recorded by Doppler
measurement in the umbilical artery reflects this
downstream impedance and is used extensively to
identify placental compromise.69
Watershed areas and the compromised
circulation
The watershed area in the brain circulation has
long been used to explain certain lesions of neonates, and a concept of a watershed at the isthmus
of the aorta, the left portal vein and the foramen
ovale with its crista dividens has been proposed
recently.
It has long been known that fetuses with critical
aorta stenosis or hypoplastic left heart syndrome
direct ductus arteriosus blood in a retrograde direction through the isthmus aortae to feed the
aortic arch. Recent studies have highlighted the
isthmus aortae as a watershed between the aortic
arch and the ductus arteriosus in anatomically
normal fetuses.70,71 Since this watershed also reflects the difference in impedance between the
cerebral circuit and that of the placenta and lower
fetal body, the blood velocity pattern across the
isthmus with various degrees of reversed flow
was suggested to be an indicator of placental
compromise.
Similarly, the direction of flow in the left portal
vein (Fig. 1) is suggested to reflect compromised
venous return demanding a compensatory increase
of blood from the main portal stem to maintain
portal and umbilical pressure, with the result being a cessation of umbilical venous flow to the
left portal branch, and, at a more advanced stage
of compromise, reversed flow that permits
splanchnic blood to enter the ductus venosus.72
A third watershed, the foramen ovale (Fig. 2),
differs from the two former watersheds. It distributes blood to the left and right atria by dividing the
ascending venous blood into two arms at the crista
dividens. The horizontal area between the foramen ovale valve and the atrial septum is thought
to be the restricting area for flow to the left atrium.50 In cases with increased venous return (e.g.
arteriovenous malformation), an increased volume
of blood is diverted to the right side, leading to increased growth of the right ventricle. In cases of
abnormally small foramen ovale, the left side of
the heart develops less in size (one of the possible
mechanisms leading to hypoplastic left heart
syndrome).
These concepts are in need of detailed studies
to make them clinically relevant.
T. Kiserud
Circulatory regulation
Circulatory responses to hypoxaemia and hypovolaemia have been particularly well studied in
animals during the last trimester of pregnancy,73
but even during mid-gestation and earlier, there
seem to be neural and endocrine responses in
addition to the prominent direct effect on cardiac
function caused by hypoxic insults.74,75 A hypoxic
insult in late pregnancy activates a chemoreflex
mediated by the carotid bodies (and, to a lesser
extent, the aortic bodies), causing an immediate
vagal effect with reduced heart rate and a sympathetic vasoconstriction.76 This is followed by
endocrine responses (e.g. adrenaline and noradrenaline) maintaining vasoconstriction (a-adrenergic), increasing heart rate (b-adrenergic) and
reducing blood volume with renin release and
increased angiotensin II concentration. The
responses involve angiotensinevasopressin mechanisms, and increased concentrations of adrenocorticotrophic hormone, cortisol, atrial natriuretic
peptide, neuropeptide Y and adrenomedullin orchestrate a circulatory redistributional pattern
that maintains placental circulation and gives priority to the adrenal glands, myocardium and
brain73 (Fig. 5). In clinical medicine, this translates
into a frequently visualized coronary circulation,77
a shift in lefteright ventricular distribution,78 a cerebral circulation with high diastolic flow,57 and an
increased impedance in the pulmonary circulation79 during circulatory compromise.
Sustained hypoxia forces an adaptational shift
to less oxygen demand, reduced DNA synthesis
Figure 5 Redistribution of fetal combined cardiac output during acute hypoxaemia caused by reduced uterine
blood flow. Based on ref.58
Physiology of the fetal circulation
and growth, with a gradual return towards
normal concentrations of blood gases and endocrine status,80 although with a residual deviation
that may have a longlasting effect on fetal and
newborn life. There is an increasing awareness
that even subtle differences in the development
of autocrine, paracrine, endocrine and metabolic
functions induced by nutritional or circulatory
variations during pregnancy could have lasting
effects with increased risks of cardiovascular
and endocrine diseases in adult life.81
Practice points
Which of the two ventricles takes a larger
volume load?
From where comes the blood in the left
atrium?
How much of the umbilical venous return is
shunted through the ductus venosus in the
human fetus?
In what sense is the aortic isthmus
a watershed?
Research directions
More information on human fetal circulation is expected to substitute animal experimental studies as the basis for
clinical medicine.
More detailed adaptational pattern is expected to give a better background for
fetal surveillance.
More detailed knowledge of human fetal
responses and adaptation is expected to
unveil the mechanisms involved in in utero
conditioning of health risk in adult life.
References
1. Brace RA. Regulation of blood volume in utero. In:
Hanson MA, Spencer JAD, Rodeck CH, editors. The circulation, Fetus and neonate. Physiology and clinical application, vol. 1. Cambridge: Cambridge University Press; 1993.
p. 75e99.
2. Nicolaides KH, Clewell WH, Rodeck CH. Measurement of fetoplacental blood volume in erythroblastosis fetalis. Am J
Obstet Gynecol 1987;157:50e3.
3. Brace RA. Fetal blood volume response to intravenous saline
solution and dextrane. Am J Obstet Gynecol 1983;143:
777e81.
501
4. Castle B, Mackenzie IZ. In vivo observations on intravascular
blood pressure in the fetus during mid-pregnancy. In:
Rolfe P, editor. Fetal physiological measurements. London,
Boston, Durban, Singapore, Toronto, Wellington: Butterworths; 1986. p. 65e9.
5. Johnson P, Maxwell DJ, Tynan MJ, Allan LD. Intracardiac
pressures in the human fetus. Heart 2000;84:59e63.
6. Ville Y, Sideris I, Hecher K, Snijders RJM, Nicolaides KH. Umbilical venous pressure in normal, growth-retarded, and
anemic fetuses. Am J Obstet Gynecol 1994;170:487e94.
7. Thornburg KL, Morton MJ. Development of the cardiovascular system. In: Thorburn GD, Harding R, editors. Textbook of
fetal physiology. Oxford: Oxford University Press; 1994.
8. Reller MD, Morton MJ, Reid DL, Thornburg KL. Fetal lamb
ventricles respond differently to filling and arterial pressures and to in utero ventilation. Pediatr Res 1987;22:
519e32.
9. Lingman G, Dahlström JA, Eik-Nes SH, Marsál K, Ohlin P,
Ohrlander S. Hemodynamic evaluation of fetal heart arrhythmias. Br J Obstet Gynecol 1984;91:647e52.
10. Rudolph AM. Distribution and regulation of blood flow in the
fetal and neonatal lamb. Circ Res 1985;57:811e21.
11. Grant DA, Fauchère JC, Eede KJ, Tyberg JV, Walker AM. Left
ventricular stroke volume in the fetal sheep is limited by
extracardiac constraint and arterial pressure. J Physiol
2001;535:231e9.
12. Rasanen J, Wood DC, Weiner S, Ludomirski A, Huhta JC.
Role of the pulmonary circulation in the distribution of human fetal cardiac output during the second half of pregnancy. Circulation 1996;94:1068e73.
13. Mielke G, Benda N. Cardiac output and central distribution
of blood flow in the human fetus. Circulation 2001;103:
1662e8.
14. Rasanen J, Wood DC, Debbs RH, Cohen J, Weiner S,
Huhta JC. Reactivity of the human fetal pulmonary circulation to maternal hyperoxygenation increases during the second half of pregnancy. Circulation 1998;97:257e62.
15. Kiserud T, Hellevik LR, Eik-Nes SH, Angelsen BAJ, Blaas H-G.
Estimation of the pressure gradient across the fetal ductus
venosus based on Doppler velocimetry. Ultrasound Med Biol
1994;20:225e32.
16. Kiserud T, Rasmussen S, Skulstad SM. Blood flow and degree
of shunting through the ductus venosus in the human fetus.
Am J Obstet Gynecol 2000;182:147e53.
17. Kiserud T, Eik-Nes SH, Blaas H-G, Hellevik LR. Ultrasonographic velocimetry of the fetal ductus venosus. Lancet
1991;338:1412e4.
18. Huisman TWA, Stewart PA, Wladimiroff JW. Ductus venosus
blood flow velocity waveforms in the human fetus e a Doppler study. Ultrasound Med Biol 1992;18:33e7.
19. Edelstone DI, Rudolph AM. Preferential streaming of ductus
venosus blood to the brain and heart in fetal lambs. Am J
Physiol 1979;237:H724e9.
20. Bellotti M, Pennati G, De Gasperi C, Battaglia FC,
Ferrazzi E. Role of ductus venosus in distribution of umbilical flow in human fetuses during second half of pregnancy.
Am J Physiol 2000;279:H1256e63.
21. Behrman RE, Lees MH, Peterson EN, de Lannoy CW,
Seeds AE. Distribution of the circulation in the normal and
asphyxiated fetal primate. Am J Obstet Gynecol 1970;
108:956e69.
22. Tchirikov M, Rybakowski C, Hünecke B, Schröder HJ. Blood
flow through the ductus venosus in singleton and multifetal
pregnancies and in fetuses with intrauterine growth retardation. Am J Obstet Gynecol 1998;178:943e9.
23. Bellotti M, Pennati G, De Gasperi C, Bozzo M, Battaglia FC,
Ferrazzi E. Simultaneous measurements of umbilical
502
24.
25.
26.
27.
28.
29.
30.
31.
32.
33.
34.
35.
36.
37.
38.
39.
40.
41.
venous, fetal hepatic, and ductus venosus blood flow in
growth-restricted human fetuses. Am J Obstet Gynecol
2004;190:1347e58.
Coceani F, Olley PM. The control of cardiovascular shunts in
the fetal and perinatal period. Can J Pharmacol 1988;66:
1129e34.
Kiserud T, Ozaki T, Nishina H, Rodeck C, Hanson MA. Effect
of NO, phenylephrine and hypoxemia on the ductus
venosus diameter in the fetal sheep. Am J Physiol 2000;
279:H1166e71.
Momma K, Takeuchi H, Hagiwara H. Pharmacological
constriction of the ductus arteriosus and ductus venosus
in fetal rats. In: Nora J, Takao A, editors. Congenital heart
disease. Causes and processes. Mount Kisco: Futura; 1984.
p. 313e27.
Loberant N, Barak M, Gaitini D, Herkovits M, Ben-Elisha M,
Roguin N. Closure of the ductus venosus in neonates: findings on real-time gray-scale, color-flow Doppler, and duplex
Doppler sonography. AJR Am J Roentgenol 1992;159:
1083e5.
Fugelseth D, Lindemann R, Liestøl K, Kiserud T, Langslet A.
Postnatal closure of ductus venosus in preterm infants % 32
weeks. An ultrasonographic study. Early Hum Dev 1998;53:
163e9.
Fugelseth D, Kiserud T, Liestøl K, Langslet A, Lindemann R.
Ductus venosus blood velocity in persistent pulmonary hypertension of the newborn. Arch Dis Child 1999;81:F35e9.
Kiserud T, Stratford L, Hanson MA. Umbilical flow distribution to the liver and ductus venosus: an in vitro investigation of the fluid dynamic mechanisms in the fetal sheep.
Am J Obstet Gynecol 1997;177:86e90.
Paulick RP, Meyers RL, Rudolph CD, Rudolph AM. Umbilical
and hepatic venous responses to circulating vasoconstrictive hormones in fetal lamb. Am J Physiol 1991;260:
H1205e13.
Tchirikov M, Kertschanska S, Schroder HJ. Differential effects of catecholamines on vascular rings from the ductus
venosus and intrahepatic veins of fetal sheep. J Physiol
2003;548:519e26.
Rudolph AM, Heymann MA, Teramo K, Barrett C, Räihä N.
Studies on the circulation of the previable human fetus.
Pediatr Res 1971;5:452e65.
Nathanielsz PW, Hanson M. Spare the brain and spoil the
liver. J Physiol 2003;548:333.
Bristow J, Rudolph AM, Itskovitz J, Barnes R. Hepatic oxygen and glucose metabolism in the fetal lamb. J Clin Invest
1982;71:1047e61.
Kiserud T, Eik-Nes SH, Blaas H-G, Hellevik LR. Foramen
ovale: an ultrasonographic study of its relation to the inferior vena cava, ductus venosus and hepatic veins. Ultrasound Obstet Gynecol 1992;2:389e96.
Volpe P, Marasini M, Caruso G, Lituania M, Marzullo A,
Volpe G. Prenatal diagnosis of ductus venosus agenesis
and its association with cytogenetic/congenital anomalies.
Prenat Diagn 2002;22:995e1000.
Rudolph CD, Meyers RL, Paulick RP, Rudolph AM. Effects of
ductus venosus obstruction on liver and regional blood flows
in the fetal lamb. Pediatr Res 1991;29:347e52.
Tchirikov M, Kertschanska S, Schroder HJ. Obstruction of
ductus venosus stimulates cell proliferation in organs of
fetal sheep. Placenta 2001;22:24e31.
Haugen G, Hanson M, Kiserud T, Crozier S, Inskip HM,
Godfrey K. Fetal liver-sparing cardiovascular adaptations
linked to mother’s slimness and diet. Circ Res 2005;96:12e4.
Haugen G, Kiserud T, Godfrey K, Crozier S, Hanson M. Portal and
umbilical venous blood supply to the liver in the human fetus
near term. Ultrasound Obstet Gynecol 2004;24:599e605.
T. Kiserud
42. Kilavuz Ö, Vetter K. Is the liver of the fetus the 4th preferential organ for arterial blood supply besides brain, heart,
and adrenal glands. J Perinat Med 1999;27:103e6.
43. Hecher K, Bilardo CM, Stigter RH, Ville Y, Hackelöer BJ,
Kok HJ. Monitoring of fetuses with intrauterine growth restriction: a longitudinal study. Ultrasound Obstet Gynecol
2001;18:564e70.
44. Baschat AA, Gembruch U, Harman CR. The sequence of
changes in Doppler and biophysical parameters as severe
fetal growth restriction worsen. Ultrasound Obstet Gynecol
2001;18:571e7.
45. Borrell A, Martinez JM, Seres A, Borobio V, Cararach V,
Fortuny A. Ductus venosus assessment at the time of nuchal
translucency measurement in the detection of fetal aneuploidy. Prenat Diagn 2003;23:921e6.
46. Matias A, Gomes C, Flack N, Montenegro N, Nikolaides KH.
Screening for chromosomal defects at 11e14 weeks: the
role of ductus venosus blood flow. Ultrasound Obstet Gynecol 1998;12:380e4.
47. Wilson AD, Rao PS, Aeschlimann S. Normal fetal foramen
ovale flap and transatrial Doppler velocity pattern. J Am
Soc Echocardiogr 1989;3:491e4.
48. Lind J, Wegelius C. Angiocardiographic studies on the human foetal circulation. Pediatrics 1949;4:391e400.
49. Lenz F, Machlitt A, Hartung J, Bollmann R, Chaoui R.
Fetal pulmonary venous flow pattern is determined by
left atrial pressure: report of two cases of left heart hypoplasia, one with patent and the other with closed interatrial communication. Ultrasound Obstet Gynecol
2002;19:392e5.
50. Kiserud T, Rasmussen S. Ultrasound assessment of the
fetal foramen ovale. Ultrasound Obstet Gynecol 2001;17:
119e24.
51. Momma K, Takao A. Increased constriction of the ductus arteriosus with combined administration of indomethacin and
betamethasone in fetal rats. Pediatr Res 1989;25:69e75.
52. Brezinka C, Huisman TWA, Stijnen T, Wladimiroff JW. Normal Doppler flow velocity waveforms in the fetal ductus arteriosus in the first half of pregnancy. Ultrasound Obstet
Gynecol 1992;2:397e401.
53. Huhta J, Cohen M, Gutgesell HP. Patency of the ductus arteriosus in normal neonates: two-dimensional echocardiography versus Doppler assessment. J Am Coll Cardiol 1984;4:
561e4.
54. Clyman RI, Mauray F, Roman C, Rudolph AM. PGE2 is a more
potent vasodilator of the fetal lamb ductus arteriosus than
is either PGI2 or 6 keto PGF1alpha. Prostaglandins 1978;16:
259e64.
55. Moise KJ, Huhta JC, Sharif DS, Ou CN, Kirshon B,
Wasserstrum N. Indomethacin in the treatment of premature labor. Effect on the fetal ductus arteriosus. N Engl J
Med 1988;319:327e31.
56. Huhta JC, Moise KJ, Fisher DJ, Sharif DS, Wasserstrum N,
Martin C. Detection and quantitation of constriction of fetal
ductus arteriosus by Doppler echocardiography. Circulation
1987;75:406e27.
57. Wladimiroff JW, Wijngaard JA, Degani S, Noordam MJ, van
Eyck J, Tonge HM. Cerebral and umbilical arterial blood
flow waveforms in normal and growth-retarded pregnancies. Obstet Gynecol 1987;69:705e9.
58. Jensen A, Roman C, Rudolph AM. Effect of reduced uterine
flow on fetal blood flow distribution and oxygen delivery.
J Dev Physiol 1991;15:309e23.
59. Sutton MSJ, Plappert T, Doubilet P. Relationship between
placental blood flow and combined ventricular output
with gestational age in normal fetuses. Cardiovasc Res
1991;25:603e8.
Physiology of the fetal circulation
60. Kiserud T, Rasmussen S, Sethi V. Fetal blood flow distribution to the placenta. Ultrasound Obstet Gynecol 2003;
22:37.
61. Gill RW. Pulsed Doppler with B-mode imaging for quantitative blood flow measurement. Ultrasound Med Biol 1979;
5:223e35.
62. Acharya G, Wilsgaard T, Berntsen GKR, Maltau JM,
Kiserud T. Reference ranges for umbilical vein blood flow
in the second half of pregnancy based on longitudinal
data. Prenat Diagn 2005;25:99e111.
63. Stembera ZK, Hodr J, Janda J. Umbilical blood flow in
healthy newborn infants during the first minutes after birth.
Am J Obstet Gynecol 1965;91:568e74.
64. Poston L. The control of bloodflow to the placenta. Exp
Physiol 1997;82:377e87.
65. Sand AE, Andersson E, Fried G. Effect of nitric oxide donors
and inhibitors of nitric oxide signalling on endothelin- and
serotonin-induced contractions in human placental arteries. Acta Physiol Scand 2002;174:217e23.
66. Poston L, McCarthy AL, Ritter JM. Control of vascular resistance in the maternal and feto-placental arterial beds.
Pharmacol Ther 1995;65:215e39.
67. Acharya G, Wilsgaard T, Berntsen GKR, Maltau JM,
Kiserud T. Reference ranges for serial measurements of umbilical artery Doppler indices in the second half of pregnancy. Am J Obstet Gynecol 2005;192:937e44.
68. Adamson SL. Arterial pressure, vascular input impedance,
and resistance as determinants of pulsatile blood flow in
the umbilical artery. Eur J Obstet Gynecol Reprod Biol
1999;84:119e25.
69. Alfirevic Z, Neilson JP. Doppler ultrasonography in high-risk
pregnancies: systematic review with meta-analysis. Am J
Obstet Gynecol 1995;172:1379e87.
70. Fouron JC, Zarelli M, Drblik P, Lessard M. Flow velocity profile of the fetal aortic isthmus through normal gestation. Am
J Cardiol 1994;74:483e6.
71. Sonesson S-E, Fouron J-C. Doppler velocimetry of the aortic
isthmus in human fetuses with abnormal velocity waveforms in the umbilical artery. Ultrasound Obstet Gynecol
1997;10:107e11.
503
72. Kiserud T, Kilavuz Ö, Hellevik LR. Venous pulsation in the
left portal branch e the effect of pulse and flow direction.
Ultrasound Obstet Gynecol 2003;21:359e64.
73. Iwamoto HS. Cardiovascular effects of acute fetal hypoxia
and asphyxia. In: Hanson MA, Spencer JAD, Rodeck CH,
editors. The circulation, Fetus and neonate physiology
and clinical application, vol. 1. Cambridge: Cambridge
University Press; 1993.
74. Iwamoto HS, Kaufman T, Keil LC, Rudolph AM. Responses to
acute hypoxemia in fetal sheep at 0.6e0.7 gestation. Am J
Physiol 1989;256:H613e20.
75. Kiserud T, Jauniaux E, West D, Ozturk O, Hanson MA. Circulatory responses to acute maternal hyperoxaemia and hypoxaemia assessed non-invasively by ultrasound in fetal sheep
at 0.3e0.5 gestation. Br J Obstet Gynaecol 2001;108:
359e64.
76. Hanson MA. Do we now understand the control of the fetal
circulation? Eur J Obstet Gynecol Reprod Biol 1997;75:
55e61.
77. Chaoui R. The fetal ‘heart-sparing effect’ detected by the
assessment of coronary blood flow: a further ominous sign
of fetal compromise. Ultrasound Obstet Gynecol 1996;7:
5e9.
78. al-Ghazali W, Chita SK, Chapman MG, Allan LD. Evidence of
redistribution of cardiac output in asymetrical growth retardation. Br J Obstet Gyanecol 1989;96:697e704.
79. Rizzo G, Capponi A, Chaoui R, Taddei F, Arduini D,
Romanini C. Blood flow velocity waveforms from peripheral
pulmonary arteries in normally grown and growth-retarded
fetuses. Ultrasound Obstet Gynecol 1996;8:87e92.
80. Bocking AD. Effect of chronic hypoxaemia on circulation
control. In: Hanson MA, Spencer JAD, Rodeck CH, editors.
The circulation, Fetus and neonate physiology and clinical
application, vol. 1. Cambridge: Cambridge University Press;
1993.
81. Barker DJP, Sultan HY. Fetal programming of human disease. In: Hanson MA, Spencer JAD, Rodeck CH, editors.
Growth, Fetus and neonate physiology and clinical application, vol. 3. Cambridge: Cambridge University Press; 1995.
p. 255e74.
Ultrasound Obstet Gynecol 2006; 28: 126–136
Published online 6 July 2006 in Wiley InterScience (www.interscience.wiley.com). DOI: 10.1002/uog.2832
Fetal cardiac output, distribution to the placenta and impact
of placental compromise
T. KISERUD*†, C. EBBING*†, J. KESSLER*† and S. RASMUSSEN*†‡
*Department of Clinical Medicine, Section of Obstetrics and Gynaecology, University of Bergen, †Department of Obstetrics and
Gynecology, Haukeland University Hospital and ‡Locus of Registry Based Epidemiology, Norwegian Birth Registry, Bergen, Norway
K E Y W O R D S: blood flow; cardiac output; circulation; echocardiography; fetus; growth restriction; placenta; ultrasound
ABSTRACT
Objectives Intrauterine growth restriction is a common
clinical problem, but the underlying hemodynamic
changes are not well known. Our aim was to determine
the normal distribution of fetal cardiac output to the
placenta during the second half of pregnancy, and to
assess the changes imposed by growth restriction with
various degrees of placental compromise.
Methods A cross-sectional study of 212 low-risk pregnancies with a gestational age of 18–41 weeks constituted the
reference population. A second group of 64 pregnancies
with an estimated fetal weight ≤ 2.5th percentile constituted the study group. Ultrasound measurements of inner
diameters and velocities at the fetal left and right ventricular outlets and intra-abdominal umbilical vein were
used to determine combined left and right cardiac output (CCO) and the fraction distributed to the placenta.
Placental compromise was graded according to umbilical
artery waveform: pulsatility index normal, > 97.5th percentile, or absent/reversed end-diastolic velocity. Regression analysis and Z-score (SD-score) statistics were used
to establish normal ranges and to compare groups.
Results During gestational weeks 18–41 the normal
CCO/kg was on average 400 mL/min/kg and the fraction
directed to the placenta was on average 32%, while after
32 weeks it was 21%. In intrauterine growth restriction
the CCO/kg was not significantly different, but the
fraction to the placenta was lower (P < 0.001). This effect
was more pronounced in severe placental compromise
(P < 0.001).
Conclusions Normally, one third of the fetal CCO is
distributed to the placenta in most of the second half
of pregnancy, and one fifth near term. In placental
compromise this fraction is reduced while CCO/kg is
maintained at normal levels, signifying an increased
recirculation of umbilical blood in the fetal body.
Copyright  2006 ISUOG. Published by John Wiley
& Sons, Ltd.
INTRODUCTION
Intrauterine growth restriction (IUGR) is one of the
major challenges in antenatal care and an important
determinant for perinatal mortality and morbidity1 . Low
birth weight has also been associated with increased risk
of cardiovascular diseases and Type 2 diabetes in adult
life2 . Although impaired maternal nutrition may influence
birth weight and health in later life, the effect on birth
weight is rather modest. This suggests that additional
powerful mechanisms, of which placental compromise
is probably the most common, are involved in the
clinically important group of growth-restricted fetuses
seen during the second and third trimesters. Experimental
data suggest that restriction in placentation leads to
impaired fetal growth3 , and a sustained reduction in
oxygen delivery imposed by a restriction in the maternal or
fetal circulation of the placenta leads to down-regulation
of DNA synthesis and fetal growth4 . In the human fetus,
IUGR and compromised placenta are commonly linked
to an augmented pulsatility of the umbilical artery. The
extreme finding of absent or reversed end-diastolic flow
(ARED) in the umbilical arteries is associated with a
perinatal mortality rate of 36%5 . These fetuses show signs
of increased afterload6 and circulatory redistribution7 .
Thus, the circulatory pattern of these fetuses is emerging,
but some fundamental pieces of information on the
underlying hemodynamics are still lacking. One of these
is the proportion of fetal cardiac output distributed to
the placenta. In 1971, Abraham Rudolph et al.8 showed
Correspondence to: Prof. T. Kiserud, Department of Clinical Medicine, Section of Obstetrics and Gynaecology, Haukeland University
Hospital, N-5021 Bergen, Norway (e-mail: [email protected])
Accepted: 29 November 2005
Copyright  2006 ISUOG. Published by John Wiley & Sons, Ltd.
ORIGINAL PAPER
Placental fraction of CCO
that, under experimental conditions, roughly one third
of the combined left and right cardiac output (CCO)
was directed towards the umbilical circulation at midgestation in human pregnancies, and a later Doppler
study9 , under physiological conditions, points in the same
direction, although a low number of observations towards
the end of pregnancy made the statistics at this point
less reliable. As for compromised pregnancies causing
umbilical hemodynamic compromise and fetal growth
impairment, the fraction of fetal CCO directed to the
placenta is not known.
The aim of this study was to determine the fetal cardiac
output and its distribution to the placenta in normal
pregnancies during the second half of pregnancy, and to
assess the changes imposed by IUGR with various degrees
of placental compromise.
METHODS
Reference population
The reference population consisted of 212 women with
low-risk pregnancies recruited, after written consent, to
a cross-sectional study acknowledged by the Regional
Committee for Ethics in Medical Research. Excluded were
those with an obstetric history of previous hypertensive
complications, IUGR, placental abruption and history of
smoking, diabetes, hypertension or any general chronic
disease. Gestational age was assessed at the routine
ultrasound examination at 17–20 weeks of gestation.
Fetuses with malformations and known chromosomal
aberrations were not included. One participant withdrew
after cardiac malformation and trisomy 21 was identified
during the study examination, and another due to social
reasons. The median gestational age at birth was 40 + 3
(range, 34 + 3 to 42 + 2) weeks. The median birth
weight was 3665 (range, 1400–4900) g, and in terms
of percentiles for the Norwegian population, it was
50th percentile (range, 1–99th percentiles). The umbilical
venous flow in this group has been presented previously
and forms the reference ranges for the present study10 .
In this study, we established new reference ranges for the
blood flow in the cardiac outlets, left–right ventricular
output differences, CCO, CCO/kg and the placental
fraction of CCO in order to compare these with the
results of growth-restricted fetuses.
IUGR group
This group consisted of 66 women recruited into
the study when fetal biometry (biparietal diameter and
middle abdominal diameter) identified an estimated fetal
weight ≤ 2.5th percentile. Gestational age was determined
by crown–rump length before 12 weeks of gestation,
biparietal diameter at the routine scan at 17–20 weeks,
or certain information of a regular last menstrual period
(LMP). In cases of a discrepancy of ≥ 10 days between
the gestational age determined by the second-trimester
scan and that calculated from a certain LMP, we relied
Copyright  2006 ISUOG. Published by John Wiley & Sons, Ltd.
127
on LMP because growth impairment was assumed to
start early, affecting size at the 17–20-week scan. Twins,
chromosomal aberrations, malformations and infections
in the present pregnancy excluded participation.
Those with a birth weight > 10th percentile were
excluded, leaving 64 for statistical analysis. These 64
had been examined at a median gestational age of
34 + 1 weeks (range, 23 + 5 to 39 + 5) weeks, and
delivered at a median gestational age of 35 + 6 (range,
25 + 0 to 40 + 6) weeks. The median lag between
examination and delivery was 3 (interquartile range
(IQR), 1–7; range, 0–85) days. The majority of neonates
were delivered by Cesarean section (47/64). In total there
were 29 girls and 35 boys, with a median birth weight
of 1870 (range, 270–3040) g. Of these, 51 were < 2.5th
percentile, seven were between 2.5th and 5th percentiles,
and six were between 5th and 10th percentiles according
to gender-specific birth-weight charts11 . Three deaths
occurred at delivery or in the delivery room (birth weights
of 270, 280 and 350 g). Of the remaining 61, seven had
an Apgar score of < 7 at 1 min and two had a score of
< 7 at 5 min, 31 were admitted to the neonatal intensive
care unit, and 19 required respiratory support.
Sonography
The participants were examined during a 45-min
session using a Vingmed CFM 800 (GE Vingmed,
Horten, Norway) ultrasound machine equipped with
a multifrequency mechanical sector transducer (center
frequency, 5 MHz) with color Doppler and pulsed
Doppler facilities (4 MHz). The spatial peak temporal
intensity was set at 45 mW/cm2 for pulsed Doppler.
The inner diameter (D) of the aorta and the pulmonary
artery was measured at an insonation angle perpendicular
to the vessel wall, between the open semilunar valves,
in a zoomed image (Figure 1). The optimal frame for
measurement was searched in the memory buffer. For the
aorta, the procedure was repeated three times or more
in 163/174 cases, and an average of 5.2 (median, 5;
IQR, 4–6; range, 1–14) times. For the pulmonary artery
the measurement was repeated three times or more in
168/177 cases, and an average of 5.5 (median, 5; IQR,
4–7; range, 1–13) times. The calculated mean diameters
were used in the statistical analysis. In a separate axial
insonation, the sample volume was placed at the ostia
of the aorta and pulmonary artery and the maximum
velocity during systole was recorded for 2–4 s during
fetal quiescence. The angle of insonation was kept as low
as possible; for the aorta it was 0◦ in 153 recordings and
the median was 10 (IQR, 2–18)◦ in the 27 remaining
recordings, while for the pulmonary artery it was 0◦ in
153 recordings and the median was 14 (IQR, 8–33)◦ in
the remaining 24. The systolic time-velocity integral (TVI)
and heart rate (HR) were calculated as an average of four
to six cardiac cycles. Left and right ventricular output
were calculated as π · (D/2)2 · TVI · HR. The CCO was
calculated as the sum of the two, and the normalized CCO
was calculated by dividing this by the fetal weight. The
Ultrasound Obstet Gynecol 2006; 28: 126–136.
Kiserud et al.
128
the 95% CI of the mean to half or less, depending on the
diameter12 . The same approach was used for the umbilical
venous flow assessment.
Statistical analysis
Figure 1 Doppler recording (a,c) and diameter measurement (b,d)
at the level of the aortic ostium (a,b) and at the pulmonary arterial
ostium (c,d) in a fetus at 30 weeks of gestation.
difference between left and right ventricular output was
calculated as a percentage of the CCO.
For the intra-abdominal umbilical vein the D was
determined as an average of four or more measurements
made before the first portal branches with an angle
of insonation perpendicular to the vessel wall10 . The
weighted mean blood velocity (Vwmean ) was recorded
during 2–4 s in a separate insonation along the axis
of the vessel with an expanded sample volume. The angle
of insonation was 0◦ in 56 recordings and the median was
16 (IQR, 10–24)◦ in the remaining 141. The fetoplacental
blood flow was calculated as π · (D/2)2 · Vwmean , and its
fraction of the CCO was calculated as a percentage.
In all fetuses, the fetal weight at the time of examination
was estimated on the basis of the weight percentile at
birth10 . In addition, the umbilical artery blood velocity
was recorded in the free loop, the pulsatility index (PIua )
was calculated from five to six waveforms, and ARED
was noted. Increasing waveform alteration was taken as
increasing hemodynamic compromise of the placenta and
the participants were grouped accordingly into those with
normal PIua , those with PIua > 97.5th percentile, and those
with ARED.
Measures were taken to restrict random error. One
person did all measurements (T.K.) in both groups. The
intraobserver variation, calculated as the coefficient of
variation for the diameter measurement, was 8.4% (95%
CI, 7.8–9.0) for the aorta and 7.7% (95% CI, 7.2–8.3)
for the pulmonary artery. The corresponding intraclass
correlations were 94% (95% CI, 92–95) and 97% (95%
CI, 96–97), respectively. In order to further control error,
the diameters were determined as a mean of three or more
repeat measurements, which we have shown to reduce
Copyright  2006 ISUOG. Published by John Wiley & Sons, Ltd.
To produce means, fractional polynomial regression
models were fitted to the ln-transformed data and
SDs were modeled by the method of scaled absolute
residuals13 . The 10th percentile was calculated as
mean − 1.282 SD and the 90th percentile as mean +
1.282 SD using back-transformed values. To achieve
a normal distribution, the outcome measures of the
growth-restricted fetuses were ln-transformed and SD
scores (Z-scores) were calculated based on ln-transformed
mean and SD values of the normally grown fetuses.
Analysis of variance and 95% CIs were used to
assess differences. P ≤ 0.05 was regarded as statistically
significant.
The intraobserver coefficient of variation for repeated
diameter measurements of the aorta and pulmonary artery
was studied in 141 and 145 participants of the reference
group with four or more observations, respectively. The
intraobserver variation was also analyzed as the intraclass
correlation. The SPSS statistical package (SPSS, Chicago,
IL, USA) was used except for the intraobserver coefficient
of variation, which was carried out according to the
‘logarithmic method’ of Bland14 .
RESULTS
Of the 210 examined successfully in the reference group,
we obtained measurements of the umbilical flow in 195
and measurements from the cardiac outlets in 181, with
complete sets in 170. Fetal movements, unfavorable
position, maternal obesity and time constraints were
the reasons for incomplete data. Of the 64 growthrestricted fetuses included, we obtained umbilical flow
measurements in 62 and measurements in the heart in
32, with complete sets for output calculation in 29. In
addition to the reasons for missing data mentioned for
the low-risk group, fetuses with IUGR were examined for
a shorter time, and priority was given to the umbilical
circulation.
Figures 2 and 3 show the diameters of the aorta
and pulmonary artery measured at the ostia between
open valves at gestational ages of 18–41 weeks. The
relationship is almost linear. In fetuses with IUGR these
diameters tended to be less than they were in the reference
group (Figures 2 and 3, Table 1). The pulmonary arterial
diameter was significantly smaller in fetuses with IUGR
and normal PIua compared with the reference group,
while the severely affected fetuses with ARED flow before
32 weeks of gestation maintained a normal pulmonary
arterial diameter (Table 1).
Normal left and right ventricular output and the results
for growth-restricted fetuses are shown in Figures 4 and 5.
Those with IUGR had lower output on both the left and
the right sides, but without significant differences between
Ultrasound Obstet Gynecol 2006; 28: 126–136.
Placental fraction of CCO
129
9
9
8
8
7
7
Aortic diameter (mm)
(b) 10
Aortic diameter (mm)
(a) 10
6
5
4
6
5
4
3
3
2
2
1
1
0
17
22
27
32
37
Gestational age (completed weeks)
0
17
42
22
27
32
37
Gestational age (completed weeks)
42
Figure 2 Diameter of the fetal aorta measured at the ostium between the open valvular leaflets in (a) 181 low-risk pregnancies and (b) 32
pregnancies with intrauterine growth restriction and various degrees of placental compromise, showing those with normal umbilical artery
pulsatility index (PI) ( ), those with PI > 97.5th percentile ( ) and those with absent or reversed end-diastolic blood velocity ( ). The
growth-restricted fetuses were different from the reference group (P < 0.001). Lines indicate 10th , 50th and 90th percentiles. The equation for
the regression line was y = 1.63336229 − 307.1038719 · GA−2 + 0.00000716359 · GA3 , and SD = 0.088581647 + 0.00122008 · GA, where
GA is gestational age in weeks. Data were ln-transformed.
10
10
Pulmonary arterial diameter (mm)
(b) 12
Pulmonary arterial diameter (mm)
(a) 12
8
6
4
2
0
17
8
6
4
2
22
27
32
37
42
Gestational age (completed weeks)
0
17
22
27
32
37
42
Gestational age (completed weeks)
Figure 3 Diameter of the fetal pulmonary artery measured at the ostium between valvular leaflets in (a) 179 low-risk pregnancies and (b) 32
pregnancies with intrauterine growth restriction and various degrees of placental compromise, showing those with normal umbilical artery
pulsatility index (PI) ( ), those with PI > 97.5th percentile ( ) and those with absent or reversed end-diastolic blood velocity ( ). The
growth-restricted fetuses were different from the reference group (P < 0.001). Lines indicate 10th , 50th and 90th percentiles. The equation for
the regression line was y = 1.687988793 − 259.8188528 · GA−2 + 0.00001134 · GA3 , and SD = 0.150728212 − 0.000965064 · GA, where
GA is gestational age in weeks. Data were ln-transformed.
Copyright  2006 ISUOG. Published by John Wiley & Sons, Ltd.
Ultrasound Obstet Gynecol 2006; 28: 126–136.
Kiserud et al.
130
Table 1 Combined cardiac output (CCO) and its distribution in intrauterine growth restriction (IUGR) compared with normal fetuses using
Z-score (SD-score) statistics
Measurement/fetus
Aortic diameter
Normal
IUGR, PIua normal
IUGR, PIua > 97.5th p.
IUGR, ARED
Aortic flow
Normal
IUGR, PIua normal
IUGR, PIua > 97.5th p.
IUGR, ARED
Pulmonary arterial diameter
Normal
IUGR, PIua normal
IUGR, PIua > 97.5th p.
IUGR, ARED
Pulmonary arterial flow
Normal
IUGR, PIua normal
IUGR, PIua > 97.5th p.
IUGR, ARED
CCO
Normal
IUGR, PIua normal
IUGR, PIua > 97.5th p.
IUGR, ARED
CCO/kg
Normal
IUGR, PIua normal
IUGR, PIua > 97.5th p.
IUGR, ARED
Left-right flow difference
Normal
IUGR, PIua normal
IUGR, PIua > 97.5th p.
IUGR, ARED
Umbilical flow
Normal
IUGR, PIua normal
IUGR, PIua > 97.5th p.
IUGR, ARED
Umbilical flow/kg
Normal
IUGR, PIua normal
IUGR, PIua > 97.5th p.
IUGR, ARED
Placenta/CCO flow fraction
Normal
IUGR, PIua normal
IUGR, PIua > 97.5th p.
IUGR, ARED
Mean
SE
95% CI
n
Overall P
0.00
−0.98
−1.06
−0.49
0.08
0.30
0.30
0.37
−0.16
−1.58
−1.66
−1.22
0.15
−0.38
−0.46
0.24
181
12
12
8
< 0.001
0.00
−0.91
−2.01
−1.03
0.08
0.29
0.31
0.39
−0.15
−1.49
−2.62
−1.79
0.15
−0.33
−1.41
−0.27
175
12
11
7
< 0.001
0.00
−1.49
−0.14
0.01
0.08
0.30
0.30
0.37
−0.15
−2.09
−0.73
−0.71
0.16
−0.90
0.45
0.74
179
12
12
8
< 0.001
0.00
−1.45
−0.70
−0.93
0.11
0.31
0.31
0.40
−0.22
−2.06
−1.30
−1.72
0.22
−0.84
−0.09
−0.13
173
12
12
7
< 0.001
0.00
−1.55
−1.75
−1.35
0.08
0.33
0.33
0.41
−0.17
−2.20
−2.40
−2.17
0.17
−0.90
−1.10
−0.53
170
11
11
7
< 0.001
0.00
0.11
−0.11
0.61
0.08
0.32
0.32
0.40
−0.16
−0.52
−0.74
−0.18
0.16
0.74
0.52
1.40
170
11
11
7
0.485
0.00
−0.32
1.07
0.23
0.08
0.31
0.31
0.39
−0.16
−0.93
0.46
−0.54
0.16
0.29
1.68
1.00
170
11
11
7
< 0.001
0.00
−1.74
−2.47
−3.88
0.08
0.24
0.24
0.30
−0.16
−2.20
−2.94
−4.46
0.16
−1.27
−1.99
−3.29
195
24
23
15
< 0.001
0.00
−0.94
−1.32
−2.00
0.09
0.25
0.26
0.32
−0.17
−1.44
−1.83
−2.63
0.17
−0.45
−0.82
−1.38
195
24
23
15
< 0.001
0.00
−0.70
−1.19
−2.68
0.08
0.31
0.31
0.39
−0.16
−1.32
−1.81
−3.45
0.16
−0.08
−0.57
−1.90
164
11
11
7
< 0.001
IUGR fetuses were grouped according to umbilical artery waveform, i.e. pulsatility index normal (PIua ), PIua > 97.5th percentile (p.), or
absent/reversed end-diastolic flow (ARED).
the three sub-groups classified according to the umbilical
artery waveform (Table 1).
Comparing left and right ventricular output (Figure 6),
there was a shift towards higher volume load in the right
ventricle, this effect being augmented during the last weeks
of pregnancy. The combined values before 32 weeks of
gestation showed a 13% greater load in the right than in
the left ventricle, and the corresponding difference after
Copyright  2006 ISUOG. Published by John Wiley & Sons, Ltd.
32 weeks was 26%. In fetuses with IUGR there was a
significant overall shift towards greater load in the right
ventricle compared with the reference group (Figure 6 and
Table 1). However, when divided into subgroups, fetuses
with IUGR and normal PIua were not different from
the reference population. On the other hand, those with
IUGR and PIua > 97.5th percentile shifted the distribution
significantly to the right compared with the reference
Ultrasound Obstet Gynecol 2006; 28: 126–136.
Placental fraction of CCO
131
900
900
800
800
700
700
Aortic flow (mL/min)
(b) 1000
Aortic flow (mL/min)
(a) 1000
600
500
400
600
500
400
300
300
200
200
100
100
0
17
22
27
32
37
0
17
42
Gestational age (completed weeks)
22
27
32
37
42
Gestational age (completed weeks)
Figure 4 Left ventricular output (aortic flow) in (a) 175 low-risk pregnancies and (b) 30 pregnancies with intrauterine growth restriction and
various degrees of placental compromise, showing those with normal umbilical artery pulsatility index (PI) ( ), those with PI > 97.5th
percentile ( ) and those with absent or reversed end-diastolic blood velocity ( ). The growth-restricted fetuses were different from the
reference group (P < 0.001). Lines indicate 10th , 50th and 90th percentiles. The equation for the regression line was
y = 6.252257178 − 974.1413866 · GA−2 + 0.00000808794 · GA3 , and SD = 0.257218688 + 0.001375273 · GA, where GA is gestational age
in weeks. Data were ln-transformed.
1800
(b) 1800
1600
1600
1400
1400
Pulmonary arterial flow (mL/min)
Pulmonary arterial flow (mL/min)
(a)
1200
1000
800
600
1200
1000
800
600
400
400
200
200
0
17
22
27
32
37
Gestational age (completed weeks)
42
0
17
22
27
32
37
Gestational age (completed weeks)
42
Figure 5 Right ventricular output (pulmonary arterial flow) in (a) 173 low-risk pregnancies and (b) 31 pregnancies with intrauterine growth
restriction and various degrees of placental compromise, showing those with normal umbilical artery pulsatility index (PI) ( ), those with
PI > 97.5th percentile ( ) and those with absent or reversed end-diastolic blood velocity ( ). The growth-restricted fetuses were different
from the reference group (P < 0.001). Lines indicate 10th , 50th and 90th percentiles. The equation for the regression line was
y = 5.825881953 − 722.6681806 · GA−2 + 0.0000236 · GA3 . and SD = 0.27653547 − 0.000171845 · GA, where GA is gestational age in
weeks. Data were ln-transformed.
group (95% CI of the Z-scores, 0.46 to 1.68 vs. −0.16
to 0.16), but also compared with those with IUGR and
normal PIua (95% CI, −0.93 to 0.29) (Table 1). Fetuses
Copyright  2006 ISUOG. Published by John Wiley & Sons, Ltd.
with IUGR and ARED in the umbilical artery showed
the same tendency but did not reach significance, their
numbers being small (Table 1).
Ultrasound Obstet Gynecol 2006; 28: 126–136.
Kiserud et al.
132
(b) 100
80
80
60
60
Left−right difference (%)
Left−right difference (%)
(a) 100
40
20
0
20
0
− 20
− 40
17
40
− 20
22
27
32
37
Gestational age (completed weeks)
− 40
17
42
22
27
32
37
Gestational age (completed weeks)
42
Figure 6 Difference between left and right ventricular output, calculated as the percentage of the combined left and right output, showing a
dominance of the right ventricle, in (a) 170 low-risk pregnancies and (b) 29 fetuses with intrauterine growth restriction. These fetuses were
subdivided to show those with normal umbilical artery pulsatility index (PI) ( ), those with PI > 97.5th percentile ( ) and those with absent
or reversed end-diastolic blood velocity ( ). The growth-restricted fetuses were different from the reference group (P < 0.001). Lines indicate
10th , 50th and 90th percentiles. The equation for the regression line was y = 5.199715945 − 0.028088562 · GA + 0.000013103 · GA3 , and
SD = 0.133574716 + 0.000029348 · GA, where GA is gestational age in weeks. Left–right flow difference + 100 was ln-transformed.
1800
1800
1600
1600
1400
1400
1200
1200
CCO (mL/min)
(b) 2000
CCO (mL/min)
(a) 2000
1000
800
1000
800
600
600
400
400
200
200
0
17
22
27
32
37
Gestational age (completed weeks)
42
0
17
22
27
32
37
Gestational age (completed weeks)
42
Figure 7 Fetal combined left and right cardiac output (CCO) in (a) 170 low-risk pregnancies, and (b) 29 pregnancies with intrauterine
growth restriction and various degrees of placental compromise, showing those with normal umbilical artery pulsatility index (PI) ( ), those
with PI > 97.5th percentile ( ) and those with absent or reversed end-diastolic blood velocity ( ). The growth-restricted fetuses were
different from the reference group (P < 0.001). Lines indicate 10th , 50th and 90th percentiles. The equation for the regression line was
y = 5.544717402 − 201.4738872 · GA−2 + 18.309430055 · GA−1 , and SD = 0.414476269 − 0.005064894 · GA, where GA is gestational age
in weeks. Data were ln-transformed.
The mean fetal CCO was 80 mL/min at 18 weeks
and 1370 mL/min at 40 weeks (Figure 7). In fetuses
with IUGR the CCO was less (Figure 7 and Table 1).
Copyright  2006 ISUOG. Published by John Wiley & Sons, Ltd.
The CCO/kg was on average 400 mL/min/kg during the
entire second half of the normal pregnancy and this
was no different from that in the group with IUGR,
Ultrasound Obstet Gynecol 2006; 28: 126–136.
Placental fraction of CCO
133
(b)
1200
1000
1000
800
800
CCO/kg (mL/min/kg)
CCO/kg (mL/min/kg)
(a) 1200
600
400
200
0
17
600
400
200
22
27
32
37
Gestational age (completed weeks)
0
17
42
22
27
32
37
Gestational age (completed weeks)
42
Figure 8 Fetal normalized combined cardiac output (CCO/kg) in mL/min/kg for (a) 170 low-risk pregnancies and (b) 29 pregnancies with
intrauterine growth restriction and various degrees of placental compromise, showing those with normal umbilical artery pulsatility index
(PI) ( ), those with PI > 97.5th percentile ( ) and those with absent or reversed end-diastolic blood velocity ( ). The growth-restricted
fetuses were not different from the normal group (P = 0.485). Lines indicate 10th , 50th and 90th percentiles. The equation for the regression
line was y = −3.137255228 + 1.794387574 · GA0.5 − 0.000015527 · GA3 , and SD = 0.205635425 + 0.000295948 · GA, where GA is
gestational age in weeks. Data were ln-transformed.
(b) 250
(a) 450
Umbilical venous flow/kg (mL/min/kg)
Umbilical venous flow (mL/min)
400
350
300
250
200
150
100
200
150
100
50
50
0
17
22
27
32
37
42
Gestational age (completed weeks)
0
17
22
27
32
37
42
Gestational age (completed weeks)
Figure 9 (a) Umbilical venous flow in 62 growth-restricted fetuses was lower than that in the reference group (P < 0.001). (b) The effect was
also present when flow was normalized for fetal weight (UV flow/kg) (P < 0.001). Growth-restricted fetuses were divided into groups,
showing various degrees of placental compromise: those with normal umbilical artery pulsatility index (PI) ( ), those with PI > 97.5th
percentile ( ) and those with absent or reversed end-diastolic blood velocity ( ). Lines indicate 10th , 50th and 90th percentiles. The equation
for the regression line for the UV flow was y = −10.08885345 + 4.68474999 · ln(GA) − 0.001042436 · GA2 , and SD = 0.337017961 −
0.000922071 · GA, and that for the regression line for the UV flow/kg was y = 4.90993362 − 27.62004561 · GA−2 − 0.000011856 · GA3 ,
and SD = 0.575534616 − 0.007815357 · GA, where GA is gestational age in weeks. All data were ln-transformed.
or any sub-group of placental compromise (Figure 8 and
Table 1).
Umbilical blood flow was less in growth-restricted
compared with normal fetuses (P < 0.001) (Figure 9), and
Copyright  2006 ISUOG. Published by John Wiley & Sons, Ltd.
there was a significant effect of increasing hemodynamic
compromise of the placenta (Table 1). This effect was less
pronounced when umbilical flow was normalized for fetal
weight, but was still significant (Figure 9 and Table 1).
Ultrasound Obstet Gynecol 2006; 28: 126–136.
Kiserud et al.
134
70
70
60
60
Placenta/CCO flow fraction (%)
(b) 80
Placenta/CCO flow fraction (%)
(a) 80
50
40
30
20
40
30
20
10
10
0
17
50
22
27
32
37
42
Gestational age (completed weeks)
0
17
22
27
32
37
42
Gestational age (completed weeks)
Figure 10 The fraction of fetal combined cardiac output (CCO) directed to the placenta calculated as a percentage of CCO (a) in 164
low-risk pregnancies. (b) The 29 fetuses with intrauterine growth restriction directed a lower proportion of CCO to the placenta
(P < 0.001), particularly in extreme degrees of compromise. Growth-restricted fetuses were divided into groups, showing various degrees of
placental compromise: those with normal umbilical artery pulsatility index (PI) ( ), those with PI > 97.5th percentile ( ) and those with
absent or reversed end-diastolic blood velocity ( ). Lines indicate 10th , 50th and 90th percentiles. The equation for the regression line was
y = 3.35420863 + 0.000060601 · GA3 − 0.000018693 · GA3 · ln(GA), and SD = 0.377370102 − 0.000755215 · GA, where GA is gestational
age in weeks. Data were ln-transformed.
The fraction of CCO directed to the placenta in
normally grown fetuses was on average 32% before
32 weeks, and 21% beyond 32 weeks (Figure 10). In
general, growth-restricted fetuses distributed less of
the CCO to the placenta (P < 0.001) (Figure 10 and
Table 1). While growth-restricted fetuses with normal
PIua distributed a similar fraction of the CCO to the
placenta compared with their normal peers, this was not
the case for those that had hemodynamic compromise.
Those with PIua > 97.5th percentile and particularly those
with ARED flow in the umbilical artery had a reduced
fraction of CCO distributed to the placenta (Table 1),
implying an increased recirculation of umbilical blood in
the fetal body.
DISCUSSION
In this study we showed that fetuses normally direct one
third of their cardiac output to the placenta during the
second half of pregnancy and one fifth during the last
couple of months. Interestingly, this implies an increase
in recirculation of umbilical blood in the fetal body
towards the end of pregnancy. Furthermore, this effect
is augmented in placental compromise. Growth-restricted
fetuses direct a reduced volume of blood towards the
placenta, both in absolute and in relative terms, while
maintaining a relatively normal cardiac output. The effect
seems to increase with the degree of placental compromise
and signifies a more extensive recirculation of umbilical
blood within the fetal body.
Copyright  2006 ISUOG. Published by John Wiley & Sons, Ltd.
The distribution of volume load within the fetal heart
also seems to be affected. Although experimental data15,16
and some studies in humans17 suggest that the normal
dominance of the right ventricle is cancelled during
challenge, our study supports that in fetuses with increased
pulsatility of the umbilical artery the right ventricle
actually takes an increased proportion of the load18,19 .
This is in keeping with other mechanisms seen in such
fetuses: reduced size of and shunting through the foramen
ovale7,20 , increased resistance in the pulmonary circuit21 ,
with correspondingly less venous return to the left heart,
and retrograde blood flow at the aortic isthmus7,22 to
further supply the aortic arch and carotid arteries with
right ventricular blood via the ductus arteriosus. A shift
to the left of the watershed area between portal and
umbilical venous supply to the liver23,24 and an augmented
blood velocity in the hepatic artery25 will change the fetal
circulation in the same direction. These are mechanisms
of redistribution but also of increased recirculation of
umbilical blood in the fetal body, which correspond to
more extensive oxygen extraction. On average, the oxygen
concentration in the umbilical vein measured in the IUGR
fetus during cordocentesis is lower than that in their
normal peers26 .
The fraction of fetal CCO directed to the placenta
found in this study is in line with the two previous
studies that examined this issue in humans, but with
an important difference: the placental fraction was less
(one fifth) near term. The study of Rudolph et al.8
using the microsphere technique found an average 33%
Ultrasound Obstet Gynecol 2006; 28: 126–136.
Placental fraction of CCO
distribution of the CCO to the placenta at mid-gestation,
but did not include higher gestational ages. Due to the
method of calculating CCO (pulmonary venous return
was not included) and the conditions not being strictly
physiological (the fetuses were exteriorized), the results
have awaited verification. Our study, applying a different
technique, presents very similar results indeed; 32% of
the CCO was directed to the placenta during gestational
weeks 18–32. In the second study, Sutton et al.9 used
Doppler ultrasound in physiological pregnancies to show
that the placental fraction of the CCO is one third
for the second half of pregnancy. Fewer numbers
included and calculation of umbilical venous flow using
maximum velocity (which tends to overestimate flow
if not corrected for the parabolic velocity profile) may
explain some of the differences from our study in late
pregnancy.
The normal fetal CCO found in our study had a
similar pattern during the second half of pregnancy to
that described in previous studies27 – 30 . Compared with
those using leading edges (inner–outer diameter) for the
vessel cross-section measurement, our results of CCO
are lower (1300 vs. 1900 mL/min at 38 weeks)29 ; our
results are more in agreement with those using inner
diameters in their calculation, as they are for CCO/kg
(400 vs. 425 mL/min/kg)30 . The 6% difference may be
ascribed to technique (this study measured between valves
at the ostium), or to chance. Knowing the variability of such measurements in the fetus31,32 , particularly
diameter measurements, we restricted error by repeating measurements12,33 and by using a single operator.
Coefficients of variation of 8.4 and 7.7%, and intraclass correlations of 94 and 97% for the diameter of the
aorta and pulmonary artery, respectively, ensured that the
study gave a fair representation of normal and abnormal
flows.
We acknowledge that having cardiac outflow measurements in less than half of the IUGR group might
represent a limitation of the study, with a possible
selection bias. A successful examination is least likely
in small fetuses with oligohydramnios in overweight
mothers; in our setting we believed that time constraints for such mothers and fetuses (which, due to
clinical reasons, tended to be examined for a shorter
period than did the low-risk group) were the main
reason for the low success rate. The fact that umbilical venous flow was obtained successfully in 62/64
cases underscores the point that due to time limitation,
the lower priority of cardiac measurements gave fewer
results.
In short, one third to one fifth of the fetal CCO
circulates the normal placenta; in comparison, the
compromised placenta shrinks this fraction, both in
absolute and in relative terms, thus driving the circulation
towards increased recirculation of umbilical blood within
the fetal body. We believe this reflects an increased
vulnerability in much the same way as does the
low oxygen concentration found in growth-restricted
fetuses.
Copyright  2006 ISUOG. Published by John Wiley & Sons, Ltd.
135
ACKNOWLEDGMENT
The study was supported by the Norwegian Research
Council.
REFERENCES
1. Kramer MS, Olivier M, McLean FH, Willis DM, Usher RH.
Impact of intrauterine growth retardation and body proportionality on fetal and neonatal outcome. Pediatrics 1990; 86:
707–713.
2. Barker DJP, Hales CN, Fall CHD, Osmond C, Phipps K,
Clark PMS. Type 2 (non-insulin-dependent) diabetes mellitus,
hypertension and hyperlipidaemia (syndrome X): relation to
reduced fetal growth. Diabetologia 1993; 36: 62–67.
3. Robinson JS, Kingston EJ, Jones CT, Thorburn GD. Studies on
experimental growth retardation in sheep. The effect of removal
of endometrial caruncles on fetal size and metabolism. J Dev
Physiol 1979; 1: 379–398.
4. Bocking AD. Effect of chronic hypoxaemia on circulation
control. Fetus and Neonate Physiology and Clinical Application,
Vol. 1, The Circulation, Hanson MA, Spencer JAD, Rodeck CH
(eds). Cambridge University Press: Cambridge, 1993; 215–224.
5. Alfirevic Z, Neilson JP. Doppler ultrasonography in high-risk
pregnancies: Systematic review with meta-analysis. Am J Obstet
Gynecol 1995; 172: 1379–1387.
6. Hecher K, Campbell S, Doyle P, Harrington K, Nicolaides K.
Assessment of fetal compromise by Doppler ultrasound
investigation of the fetal circulation. Circulation 1995; 91:
129–138.
7. Mäkikallio K, Jouppila P, Räsänen J. Retrograde aortic isthmus
net blood flow and human fetal cardiac function in placental
insufficiency. Ultrasound Obstet Gynecol 2003; 22: 351–357.
8. Rudolph AM, Heymann MA, Teramo K, Barrett C, Räihä N.
Studies on the circulation of the previable human fetus. Pediatr
Res 1971; 5: 452–465.
9. Sutton MSJ, Plappert T, Doubilet P. Relationship between
placental blood flow and combined ventricular output with
gestational age in normal fetuses. Cardiovasc Res 1991; 25:
603–608.
10. Kiserud T, Rasmussen S, Skulstad SM. Blood flow and degree
of shunting through the ductus venosus in the human fetus. Am
J Obstet Gynecol 2000; 182: 147–153.
11. Skjaerven R, Gjessing HK, Bakketeig LS. Birthweight by gestational age in Norway. Acta Obstet Gynecol Scand 2000; 79:
440–449.
12. Kiserud T, Saito T, Ozaki T, Rasmussen S, Hanson M. Validation of diameter measurements by ultrasound. Intra-observer
and inter-observer variation assessed in vitro and in the fetal
sheep. Ultrasound Obstet Gynecol 1999; 13: 52–57.
13. Royston P, Wright EM. How to construct ‘‘normal ranges’’ for
fetal variables. Ultrasound Obstet Gynecol 1998; 11: 30–38.
14. Bland JM. How should I calculate a within-subject coefficient
of variation? http://www-users.york.ac.uk/∼mb55/meas/cv.htm
[Accessed 22 September 2005].
15. Thornburg KL, Morton MJ. Filling and arterial pressures as
determinants of RV stroke volume in the sheep fetus. Am J
Physiol 1983; 244: H656–H663.
16. Rudolph AM. Distribution and regulation of blood flow in the
fetal and neonatal lamb. Circ Res 1985; 57: 811–821.
17. al-Ghazali W, Chita SK, Chapman MG, Allan LD. Evidence
of redistribution of cardiac output in asymmetrical growth
retardation. Br J Obstet Gynaecol 1989; 96: 697–704.
18. Reed KL, Anderson CF, Shenker L. Changes of intra-cardiac
Doppler blood flow velocities in fetuses with absent umbilical
artery diastolic flow. Am J Obstet Gynecol 1987; 157: 774–779.
19. Weiner Z, Farmakides G, Schulman H, Penny B. Central and
peripheral hemodynamic changes in fetuses with absent
end-diastolic velocity in umbilical artery: Correlation with
Ultrasound Obstet Gynecol 2006; 28: 126–136.
136
20.
21.
22.
23.
24.
25.
26.
computerized fetal heart rate pattern. Am J Obstet Gynecol
1994; 170: 509–515.
Kiserud T, Chedid G, Rasmussen S. Foramen ovale changes in
growth-restricted fetuses. Ultrasound Obstet Gynecol 2004; 24:
141–146.
Rizzo G, Capponi A, Chaoui R, Taddei F, Arduini D, Romanini C. Blood flow velocity waveforms from peripheral
pulmonary arteries in normally grown and growth-retarded
fetuses. Ultrasound Obstet Gynecol 1996; 8: 87–92.
Sonesson S-E, Fouron J-C. Doppler velocimetry of the aortic
isthmus in human fetuses with abnormal velocity waveforms
in the umbilical artery. Ultrasound Obstet Gynecol 1997; 10:
107–111.
Kiserud T, Kilavuz Ö, Hellevik LR. Venous pulsation in the
left portal branch – the effect of pulse and flow direction.
Ultrasound Obstet Gynecol 2003; 21: 359–364.
Kilavuz Ö, Vetter K, Kiserud T, Vetter P. The left portal vein is
the watershed of the fetal venous system. J Perinat Med 2003;
31: 184–187.
Kilavuz Ö, Vetter K. Is the liver of the fetus the 4th preferential
organ for arterial blood supply besides brain, heart, and adrenal
glands. J Perinat Med 1999; 27: 103–106.
Soothill PW, Nicolaides KH, Campbell S. Prenatal asphyxia,
hyperlactaemia and erythroblastosis in growth retarded fetuses.
Copyright  2006 ISUOG. Published by John Wiley & Sons, Ltd.
Kiserud et al.
BMJ (Clin Res Ed) 1987; 294: 1051–1053.
27. Kenny JF, Plappert T, Saltzman DH, St John Sutton MG.
Changes in intracardiac blood flow velocities and right and left
ventricular stroke volumes with gestational age in the normal
fetus. Circulation 1986; 74: 1208–1216.
28. De Smedt MCH, Visser GHA, Meijboom EJ. Fetal cardiac
output estimated by Doppler echocardiography during midand late gestation. Am J Cardiol 1987; 60: 338–342.
29. Rasanen J, Wood DC, Weiner S, Ludomirski A, Huhta JC. Role
of the pulmonary circulation in the distribution of human fetal
cardiac output during the second half of pregnancy. Circulation
1996; 94: 1068–1073.
30. Mielke G, Benda N. Cardiac output and central distribution
of blood flow in the human fetus. Circulation 2001; 103:
1662–1668.
31. Beeby AR, Dunlop W, Heads A, Hunter S. Reproducibility of
ultrasonic measurement of fetal cardiac haemodynamics. Br J
Obstet Gynaecol 1991; 98: 807–814.
32. Simpson JM, Cook A. Repeatability of echocardiographic
measurements in the human fetus. Ultrasound Obstet Gynecol
2002; 20: 332–339.
33. Kiserud T, Rasmussen S. How repeat measurements affect
mean diameter of the umbilical vein and the ductus venosus.
Ultrasound Obstet Gynecol 1998; 11: 419–425.
Ultrasound Obstet Gynecol 2006; 28: 126–136.
Diabetes
i svangerskapet
Hva er diabetes?
En tilstand der blodsukkeret i fastende og/eller
ikke-fastende tilstand er over et definert nivå
Grunnkurs i Obstetrikk
2016
Tore Henriksen
Fødeseksjonen, Rikshospitalet
Oslo Universitetssykehus
Hvorfor blir blodsukkeret for høyt?
Blodglukosens kilde nr 1: Tarm
Etter måltid
Kort om omsetningen (metabolismen) av
glukose
Blodglucose
Tarm
Kilde nr 2: Lever
De kvantitativt viktigste forbrukere av glukose
I fastende tilstand
Lever
Glykogen!
Insulin?
Glukoneogenese
(ved faste)
Blodglucose
Blodglucose
Hjerne
Tarm
Fettvev
Tarm
Muskel
Muskulatur og fettvev sammen med lever er sentrale
i regulering av blodsukkeret
Opptaket av glukose i muskel og fettvev er
avhengig av at Insulin-systemet virker
Glykogen!
Glykolyse
Glukoneogenese
Insulin
Insulin
Glukose
Glukose
Blodglucose
Blodglucose
Insulin
Insulin
Hjerne
Fettvev
Muskel
Tarm
Fettvev
Tarm
Muskel
Insulin-systemet kan svikte på to måter
Insulin-systemet kan svikte på to måter
Insulin
1. Svikt i pancreas’øyceller
Glykolyse
Glukoneogenese
Glykolyse
Glukoneogenese
Insulin
Glukose
Glukose
Blodglucose
Fettvev
Blodglucose
Muskel
Tarm
Fettvev
Tarm
Muskel
Type 1 diabetes: for lite insulin
Insulin-systemet kan svikte på to måter
1. Svikt i pancreas’øyceller
Glykolyse
Glukoneogenese
Glykolyse
Glukoneogenese
Insulin
Insulin
Glukose
Glukose
Blodglucose
Blodglucose
2. Insulinet virker ikke på
cellenivå (insulinresistens)
Fettvev
Tarm
Muskel
Fettvev
Tarm
Muskel
Type 2 diabetes:
Ofte høyt insulin, men insulin resistens,
gjerne kombinert med en relativ
svikt i øycellene
Øycelleinsuffisiens
Glykolyse
Glukoneogenese
Klassifikasjon av diabetes/glukoseintoleranse
i svangerskapet
 Pregestasjonell diabetes,
(“kjent diabetes”)
Insulin
Glukose
Blodglucose
2. Insulinet virker ikke på
cellenivå (insulinresistens)
Fettvev
Tarm
 Diabetes/glukoseintoleranse) oppdaget
første gang i svangerskapet
•
•
•
•
Type 1 diabetes. (IDDM)
Type 2 diabetes (økende!)
Nyoppdaget Type 1 og tType 2 diabetes
Svangerskaps-(gestasjonell) diabetes
Muskel
Diabetes/glukoseintoleranse: Definisjoner
(WHO/kriterier, 1999, men NYE ER PÅ VEI!)
PREGESTASJONELL DIABETES
Forekomst/epidemiologi.
250 -300 kvinner med Type 1 diabetes
og
ca 150-200 med Type 2
gjennomfører et svangerskap per år i Norge.
Gravide med pregestasjonell diabetes
(Type 1 eller Type 2)
1. Godt regulert diabetes før de blir gravide!!,
eventuell prekonsepsjonell veiledning. Komorbiditet?
Kost, vekt og mosjon!
HbA1c <7 før svangerskapet
Folat fra det tidspunkt en kvinne ønsker å bli gravid
Hvis antihypertensiva: Bruk (skift til) labetolol (event nifedipin
eller metyldopa)
Oppgave for primær og spesialisthelsetjenesten
Spesialisthelsetjenesten: Vurdering (prekonsepsjonelt) av dem
som bruker metformin (event insulinanaloger)
Plasma glukose nivå
mmol/l
Manifest Diabetes Mellitus:
Fastende
 7.0
eller
2 t etter 75g glukose oralt
Svangerskapsdiabetes (GDM):
Fastende
og
2 t etter 75 g glukose oralt
 11.1
 5.3, men <7.0
 9.0, men <11.1
Metformin ved type 2 diabetes?
• Synes ikke teratogent
• Men: noe usikkerhet m h p metabolsk langtidseffekt på barnet
Brukes i praksis når det er klar indikasjon der fordeler
og usikkerhet er vektet.
Pregestasjonell diabetes
Oppfølging i svangerskapet:
Spesialistoppgave
Komplikasjoner:
Gravide med pregestasjonell diabetes (type
1 eller type 2)
(eller nyoppdaget insulinkrevende
gestasjonell diabetes):
1. Misdannelser (både type 1 og type 2!)
(HbA1c >8: tidlig/utvidet ultralyd)
2. Preeklampsi
3. Føtale vekstavvik (intrauterin veksthemning/makrosomi)
4. Økt perinatal mortalitet
Oppfølging av pregestasjonell (type 1 og 2)
diabetes i svangerskapet
Henvises til fødepoliklinikk så raskt som mulig etter at graviditeten er bekreftet.
På Fødepoliklinikken:
1. Generell gjennomgang (som ved pregestasjonell veiledning) + tidligere svangerskap
Oppfølging av pregestasjonell (type 1 og 2)
diabetes i svangerskapet, forts.
7. Blodglukosemåling før og etter hovedmåltidene og ved sengetid.
Behandlingsmål:
Blodglukose 3,5 – 5,5 mmol/l før måltid og under 7,0 mmol/l målt 1½-2 timer etter måltid.
HbA1c < 6.0 % i 2. og 3. trimester.
2. HbA1c ≥ 8 % (nå eller rett før graviditeten): tilbys ekstra «utvidet ultralyd» i uke 15-16,
i tillegg til den ordinære ultralydscreeningen noen uker senere
8. Hvis skifte fra metformin til insulin tidlig i svangerskapet: Obs hyperglykemi!
3. Urin dyrkning ved 1. kontroll?
9. Ved kostregulert Type 2: Blodsukkermåling fastende og ca 1.5 timer post-prandialt
hver annen dag. Medisinsk behandling foreslås hvis pasienten i løpet av en uke har til
sammen flere enn 2 målinger av enten fastende blodsukker > 5.5mmol/l eller
> 7mmol/l postprandialt.
4. HbA1c måles hver 4. uke.
5. BT og stix; protein/ kreatinin ratio i urin med 4-6 ukers intervall.
6. Diabetes > 5 år: obs øyelege
11. Kostråd og mosjonståd. Se www.helsedirektoratet.no for generelle kostråd,
for diabetes og for gravide.
skapsuke
6
X
7
Obetetriske momenter i oppfølgingen av pregetasjonell
Kontrollhyppighet,
Insulinkrevende diabetes
8
X X
X
9
10
X
11
• Reperterte tilvekstmålinger (ca hver 4. uke) fra ca uke 24.
• Tegn til avtakende tilvekst (vektmessig) eller tegn
til begynnende assymetri er alltid alvorlig selv om barnet er
er ”normalt stort”. Snikende placentasvikt kan sees hos store barn!
• Fostervannsmengde i nedre normalområde eller tegn til avtakende
fostervannsmengde, selv om det er innenfor refranseverdiene.
skal alltid vektlegges.
• Doppler: Sentralisering? (arteria cerebri media)
• CTG vektlegges: Obs: Basalfrekvens (endring?), kortidsvariabilitet
(Oxford 8002), reaktivitet (akselerasjoner).
• Bevegelser?!
• Preeklampsi-utvikling ved pregestasjonell diabetes alltid alvorlig
(placentasvikt slev om barnet er normal eller stort).
12
X
14
X
16
X
18
X
20
X
22
X
24
X
26
X
28
X
30
X
X Evt. UL fosterm
Scr. v/jordmor
X
X
X
X
X
X
X
X
X
X
X
X
31
32
Inidkasjon
33
34
inidikasjon
35
36
37
38
X
39
40
X
X
X
X
X
X
X
X Vurdering
X
X
X
X Vurdering
X
Truende preterm fødsel ved insulinkrevende diabetes.
Absolutt risiko ca 15 %.
Rihemmende behandling ved diabetes i svangerskapet
Atosiban (Tractocile) Blodsukkeret skal følges, da atosiban kan gi blodsukkerstigning.
Induksjon av fødsel ved pregestasjonell diabetes:
Induksjon vurderes fortløpende fra ca 38 fulle uker. Anbefales ikke å gå over termin.
Keisersnitt: Vanlige obstetriske indikasjoner. Ved alvorlige vaskulære, nyre eller øyekomplikasjoner etter
individuell vurdering. Keisersnitt vurderes ved
mistanke om vekt over 4500g*.
Celeston
i to doser med (12-)24 timers intervall. Økt behov for
insulin Økningen gjelder både hurtig og langsomtvirkende insulin.
Forslag til dosering av insulin økes fra dag 2:
Dag 1 (Dagen etter første dose Celeston). Ingen endring av insulindose
Dag 2 30 % økning av den opprinnelige insulindosen
Dag 3 40 % økning av den opprinnelige insulindosen
Dag 4 20 % økning av den opprinnelige insulindosen
Dag 5 10 % økning av den opprinnelige insulindosen
Dag 6 Vanlig insulindose
Ved blodsukker over 8 mmol/l gis ekstra hurtigvirkende insulin (4-6 enheter).
Aktiv fødsel, Insulinkrevende diabetes
Ved tidligere skulderdystoci keisersnitt vurderes mistanke om vekt over 4000g*
*OBS! Vektestimering usikker business! Flere målinger over flere uker for å øke sannsynligheten for
riktigere estimat. Se på AC-målet!
Aktiv fødsel, insulinkrevende diabetes
Tiltak ved ulike blodsukkernivåer:
Blodsukkermåling ca hver time, eventuetl oftere, individuell vurdering.
Mål blodglukose: 4-7 mmol/l.
Insulin:
Pasientens egen erfaring med insulin!
LAVT blodsukker:
Pasienten er bevisstløs eller kraftig føling: Glucose 200 mg/ml 40 ml i.v. i støt.
Dosen gjentas hvis pasienten ikke kommer til bevissthet i løpet av 10.
Blodsukker er under 4,0 mmol/l: Gi glucose 50 mg/ml i.v. infusjon etter kroppsvekt:
60 kg: 180 ml/t
80 kg: 250 ml/t
100 kg: 300 ml/t
HØYT blodsukker:
Blodsukker 8,0-10,0 mmol/l: 2- 4 E hurtigvirkende insulin s.c.
Gjentas etter 2 timer hvis fortatt er for høyt:
Blodsukker over 10,0 mmol/l : 4-8 E hurtigvirkende insulin s.c.
Eventuelt gjentas etter 2 timer.
Klassifikasjon av diabetes/glukoseintoleranse
i svangerskapet
Svangerskapsdiabetes (GDM)
Nye retningslinjer:
Definisjoner
Hvordan finne de som har GDM («screening»)
Oppfølging
Fødsel
 Pregestasjonell diabetes,
(“kjent diabetes”)
•
•
 Diabetes/glukoseintoleranse oppdaget
første gang i
svangerskapet
A. Nyoppdaget Diabetes:
Type 1 (sjelden) eller Type 2
Type 1 diabetes. (IDDM)
Type 2 diabetes (økende!)
B. Svangerskapsdiabetes (GDM)
Klassifikasjon av diabetes/glukoseintoleranse
i svangerskapet
 Pregestasjonell diabetes,
(“kjent diabetes”)
•
•
 Diabetes/glukoseintoleranse oppdaget
første gang i
svangerskapet
A. Nyoppdaget Diabetes:
Type 1 (sjelden) eller Type 2
Type 1 diabetes. (IDDM)
Type 2 diabetes (økende!)
B. Svangerskapsdiabetes
Svangerskapsdiabetes (GDM) er en tilstand med glukoseintoleranse som diagnostiseres
i svangerskapet, men der glukoseintoleransen ikke er av en slik grad at kriteriene for diabetes
(«ekte diabetes», «manifest diabetes») oppfylles.
Diagnosen (definisjonen av) svangerskapsdiabetes baseres resultatet av en glukosebelastning (75 g etter minst 8 timers faste):
Fastende glukose: ≥ 5.3, men ≤ 6.9 mmol/l
og/eller
2‐timers verdi ≥ 9.0, men ≤ 11.0 mmol/l
Hvis fastende glukose er ≥ 7.0 og eller 2‐timers verdien ≥11.1 mmol/l,
har pasienten diabetes!
Fem sentrale tanker ligger bak de nye retningslinjene for GDM
1. Grunnlaget for den nye definisjonen av GDM er ny.
2.GDM skal sees i en helhet, d v s sammen med overvekt/fedme og livsstil
«To sider av samme mynt»!)
2.En vil finne de med tidlig innsettende svangerskapsdiabetes, fordi disse har størst
risiko for GDM‐relaterte svangerskapskomplikasjoner (preeklampsi, makrosomi) og
trenger oftere insulin
Grunnlaget for definisjonen av GDM
Risikoen for uheldige svangerskapsutfall, f eks store barn (LGA), er lineært relatert til plasmaglukosen
HAPO-studien
til mors plasmaglukose
N Engl J Med 2008
Det er ingen ”breake point(s)”, sammenhengen mellom blodsukkerverdiene og
uheldige utfall er kontinuerlig, altså ikke‐kategorisk!
3.En har beveget seg bort fra screening av risikogrupper og heller basere seg på å
teste alle, med unntak av de med svært lav risiko (se senere)
4.Testingen baserer seg på
a) måling av HBA1c (1. trimester) og b) senere glukosebelastning ved 26‐30 uker (se senere)
Grunnlaget for definisjonen av GDM
Risikoen for uheldige svangerskapsutfall, f eks store barn (LGA), er lineært relatert til plasmaglukosen
HAPO-studien
til mors plasmaglukose
N Engl J Med 2008
Grunnlaget for definisjonen av GDM
Risikoen for uheldige svangerskapsutfall, f eks store barn (LGA), er lineært relatert til plasmaglukosen
HAPO-studien
til mors plasmaglukose
N Engl J Med 2008
Nå har vi valgt de (fastende og 2 timers) glukoseverdiene som medfører en dobling (Odds ratio=2) av uheldige svangerskapsutfall (makrosomi eller preeklampsI)
Odds ratio=2
Hvorfor akkurat
denne verdien?
Nåværende
WHO fastende glukose verdi
Fastende ≥ 5.3 og 2–timers ≥ 9.0
Ved første kontroll (1. trimester):
GDM skal sees i en helhet:
Før svangerskapet (pregestasjonell veiledning):
A.Rådgivning for å redusere risikoen for GDM (kost, fysisk, vektreduksjon)
B.Vurdere HBA1c, eventuelt glukosebelastning, hos kvinner med
høy risiko for diabetes (betydelig familiær belastning, fedme/
metabolsk syndrom, tidligere GDM, barn fødselsvekt over 4500g)
Ta HBA1c av alle, unntatt de med «svært lav risiko».
«Svært lav risiko»: Europeisk bakgrunn, generelt frisk, <25 år, BMI<25, ikke diabetes i familien, tidligere ukompliserte svangerskap
Tiltak basert på HBA1c funn i 1. trimester:
HBA1c <5.9%: ingen videre tiltak før glukosebelastning ved 26‐30 uker
(men hvis overvektig likevel, livsstilsråd!)
HBA1c ≥ 6.5 %: Diabetes!
HBA1c ≥ 5.9%, men ≤ 6.4%: Obs! Sjekk risikofaktorer igjen. Råd!
HBA1c ≥ 5.9%: Til spesialisthelsetjenesten. Obs: hvis HBA1c ≥ 6.5% har hun diabetes. Det må komme tydelig frem når pasienten henvises. Videre oppfølging i primærhelsetjenesten av de som har normal HBA1c (< 5.9 %):
Vanlig oppfølging.
MEN: ved 26‐30 uker tas
Glukosebelastning på alle, unntatt de med «svært lav risiko»
«Svært lav risiko»: Europeisk bakgrunn, generelt frisk, <25 år, BMI<25, ikke diabetes i familien, tidligere ukompliserte svangerskap
Videre tiltak basert på glukosebelastningen:
Hvis fastende verdi < 5.3 mmol/l: kontrollen fortsetter i primærhelsetjenesten. Ved eventuelt
senere glukosuri: ingen tiltak.
I spesialisthelsetjenesten
(de med HbA1c ≥ 5.9%, men <6.5% eller patologisk glukosebelastning
ved 26‐30 uker (fastende ≥ 5.3, men ≤ 6.9 mmol/l og/eller 2‐timers verdi ≥ 9.0, men ≤ 11.0 mmol/l):
Oppplæring i egenmåling av blodglukose og kost og livsstilsråd
Målet ved kost‐ og andre livsstilstiltak: a)Før måltid (preprandialt) < 5.3 og b)Etter måltid (postprandialt) <6.7 mmol/l
Hvis målene oppnås med livsstilstiltak, kan pasienten fortsette i primærhelsetjenesten
Hvis fastende glukose: ≥ 5.3 og/eller 2‐timers verdi ≥ 9.0,mmol/l:
Henvis spesialisthelsetjenesten.
Obs: Hvis fastende glukose er ≥ 7.0 og eller 2‐timers verdien ≥11.1 mmol/l,
har pasienten diabetes! Det må komme tydelig frem når pasienten henvises. Hvis 3‐4 blodglukoseverdier er over disse verdiene i løpet av ca 2 uker er medikamentell behandling aktuelt (insulin
eller metformin). Spesialistoppgave.
Obstetrisk oppfølging ved svangerskapsdiabetes (GDM)
Vektøkning i svangerskapet ved GDM:
Følger generelle retningslinjer
Institute of Medicine (IOM) retningslinjer:
BMI
BMI
BMI
BMI
a
(<20):
(20-25.9):
26-29:
>30:
12.5-18 kg
11.5-16 kg
7-11 kg
5-9 kg
Men: Ved BMI 30‐35 reduseres risikoen for noen uheldige svangerskapsutfall (preeklampsi, makrosomi) ved vektøkning 0‐6 kg, kanskje litt økning av SGA
Ved BMI over 35 forslås vektøkning på 0‐5 kg. I praksi vil noen gå noe ned i vekt. Det er akseptablet fortutsatt adekvat sammensatt kost og tilvekstkontroll slik som anbefalt
OBS: mangelen vektøkning kan bety placentasvikt, derfor ultralydskontroll slik som anbefalt
Alltid ultralyd ved første konsultasjon i spesialisthelsetjenesten, uansett gestasjonsalder
Ved tidlig innsettende GDM gjøres alltid ultralyd ved 23‐25 uker
For pasienter som fortsetter i spesialist helsetjenesten gjøres
(etter 23‐25 uker) ultralyd generelt med 4‐6 ukers intervaller.
Hvis pasienten går tilbake til primærhelsetjenesten henvises pasienten til ultralyd ved 31‐33 uker og ved 36‐37 uker for vekstkontroll. Det gjøres også CTG ved 36 uker. Videre oppfølging individualiseres (se nedenfor)
Oppfølging etter ca 36 uker. Induksjon.
Viktige momenter ved vurder av GDM, spesielt etter 36 uker
De som er godt regulert på kost og livsstilstiltak:
A. Hvis AC eller MAD er stigende til over 90p eller fallende til under 10p ved 36 uker gjøres ny ultralyd og CTG etter individuelle vurdering (komorbiditet? tidligere obstetrisk sykehistorie?BT/urin ? Fostervann?
Doppler? (as)symmetri?). Induksjon etter individuell vurdering
B. Ved fravær av relevant komorbiditet, godt regulert blodglukose, normal tilvekst (ikke akselererende) og normale biofysiske funn ellers, inklusive CTG, går de tilbake til primæhelsetjenesten.
Kontrolleres de i løpet av første uke etter termin. Ved normale funn følges vanlige overtidsregler
Medikamentelt behandlet GDM
CTG gjøres ukentlig fra og med ca uke 36, før det på indikasjon
Generelt gjøres ny ultralyd ved uke 38.
Induksjon vurderes etter ca 38 uker. Generelt bør denne gruppen være indusert innen termindato Rask fostervekst henimot termin (akselererende AC eller MAD over 90 percentilen ) medfører økt risiko for fosterdød sannsynligvis p g a en relativ placentasvikt. Denne risikoen øker ved stigende blodtrykk/preeklampsi.
PI i art umb kan være normal, men ved økende hypoksi vil endringen PI i art cerebri media falle og etter hvert PI i Ductus venosus øke.
CTG påvirkes ved økende hypoksi og er en sentral undersøkelse ved mistanke om relativ placentasvikt.
Fostervannsmengde i nedre normalområde hos et makrosomt barn kan bety «relativ oligohydramnion».
Fosterbevegelser (anamnestisk og ved undersøkelsen) må også tillegges betydelig vekt.
Fedme
Tre hovedbudskap:
Tore Henriksen
Fødeseksjonen, Rikshospitalet
OUS
I: Fedme (adipositas) gir økt risiko for komplikasjoner i
svangerskapet, fødsel og barseltid.
II: Det transgenerasjonelle perspektivet:
Effekten av det intrauterine miljø på neste
generasjon(er)
III. Den mest effektive måten å unngå fedme-relaterte
komplikasjoner for mor og barn er å sikre en sunn
livsstil og unngå fedme før svangerskapet inntrer
Hvordan skaffer man seg kunnskap om det hjelper med tiltak
for overvekt/fedme?
1. Fysiologisk kunnskap. For eksempel: Høyt blodsukker
hos mor gir høyt blodsukker og høyt insulin hos barnet,
som medfører høyt neonatalt kroppsfett
2. Klinisk erfaring. For eksempel: Reduser sukkerinntak
i siste trimester stopper ofte en akslererende vekst av
fostrets abdominalmål
3. Studier av befolkningsgrupper (populasjoner)
Det går en grunnleggende forskjell
mellom
A. Observasjonsstudier
og
B. Intervensjonsstudier (clinical trials)
A. Observasjonsstudier
B. Intervensjonsstudier
Observasjonsstudier f eks forekomsten av
Svangerskapsdiabetes (GDM)
Normalvektige
Normalvektige
Oddsen her kan være
2 av 100 for GDM
Svangerskapsdiabetes, forekomst
(prevalens).
BMI over 30
Oddens her kan være
6 av 100 for GDM
Observasjonsstudier
Observasjonsstudier beskriver statistiskeSvangerskapssammenhenger
mellom variable (f eks mellom fedme og diabetes),
diabetes, forekomst.
men sier ikke nødvendig noe om årsakssammenheng.
BMI>30
RISIKOEN for å få GDM
kan da angis som
ODD RATIO (OR), som er:
OR:
6
2
94
98
=3.1
Årsak?
Overvekten (BMI)?
Fordelingen av kroppsfett?
Liten fysisk aktivitet?
Miljøgifter?
Ulik genetisk aktivitet (epigenetikk?)
Gener?
Intervensjonsstudier
(randomisert studier, clinical trials)
Observasjonsstudier viser tydelig at
Studiepopulasjon:
Kontrollgruppe
Gravide
Overvekt/fedme, vektøkning i svangerskapet og blodglukose (diabetes)
Endepunkt
(utfall,
outcome):
Loddtrekning
F eks.:
Svangerskapsdiabetes
Intervensjonsgruppe
a) Overvekt/fedme, b) høy vektøkning i svangerskapet c) Høyt blodsukker/diabetes hver for seg, og ikke minst sammen,
Gruppene
blir like
(alderkjønn,vekt,
udannelse etc )
øker risikoen for svangerskapskomplikasjoner og for sykdom hos mor og barn lengre sikt.
Intervensjon:
Kost og Fysisk aktivitet
Risk of LGA (>90p) according to Maternal obesity,
Gestational diabetes (GDM) and
high Gestational Weight Gain (GWG)
Overweight/obesity and pregnancy.
Short and long term outcomes
Bowers K et al Diabetologia 2013
10
Short term
Consequences
(mother/child)
Risk of LGA
Odds ratio
Overweight/obesity
Metabolic syndrome
High blood glucose/
Diabetes
High weight gain
• Miscarriage
• Preterm birth
• Preeclampsia
• Gestational diabetes
• Thromboembolism
• Congential malformations
• Intrauterine fetal death
• Delivery complications
(Prolonged labour, Fetal
distress, Vacuum/forceps,
Cesarean section)
• Neonate injuries
• Maternal injuries/infections
• Need for neonatal
intensive care
• Less breast feeding
Long term
consequences
0
GDM GWG Obesity
GDM
+GWG
Obesity
+GWH
GDM
+obesity
BMI og risiko for fosterdød
GDM +obesity+ GWG
• Maternal
Overweight
Diabetes
Anal dysf.
• Child
Diabetes
Overweight
Cancer
Cardiovascular
disease
Overweight/obesity and
pregnancy outcomes Observational studies: Cesarean section: Dose‐response
Barau G et al BJOG 2006:
Emergency Cesarean delivery: Obese versus ideal weight*
Heslehurst N et al Obes Rev 2008
Maternal pre-pregnancy BMI and fat mass index
in the child at age of nine years
Gale CR et al 2007 J Clin Endocrinol Meatbol
at 9
years
at 9
years
* BMI >30kg/m2 versus BMI 20‐25
Overvekt/fedme hos gravide
1. Det er ingen tvil om at:
Tilstanden fedme er en betydelig
risikofaktor for svangerskapskomplikasjoner
og helse senere (funnet ved observasjonelle
studier)
Men:
2. Hjelper det å intervenere i svangerskapet?
Interventional studies
Total gestational weight gain
following dietary and/or physical
activity intervention
(in a general population)
Interventional studies
Total gestational weight gain
following dietary intervention only
(in a general population)
The 2012 metaanalysis 2: Thangaratinam S et al BMJ May 2012
The 2012 metaanalysis 2: Thangaratinam S et al BMJ May 2012*
Ved intervensjon med kost og fysisk aktivitet kan
vektøkningen i svangersapet reduseres
* Studyca
population:
med
1-2kg Any BMI  18.5 kg/m2
Diett synes å ha størst effekt (i
svangerskapet)
Interventional studies
Pregnancy complications
gain following dietary intervention during pregnancy
(in a general population)
The 2012 metaanalysis: Thangaratinam S et al BMJ May 2012
Interventional studies
SGA and LGA
following dietary intervention during pregnancy
(in a general population)
The 2012 metaanalysis: Thangaratinam S et al BMJ May 2012
Preeclampsia:
Gestational
Diabetes:
Liten effekt på forekomsten av store barn (LGA).
Ingen flere små barn (SGA)
Preterm
Delivery:
Interventional studies
Mean birth weight
following dietary intervention during pregnancy
Interventional studies
Neonatal outcomes
gain following dietary intervention during pregnancy
(in a general population)
(in a general population)
The 2012 metaanalysis: Thangaratinam S et al BMJ May 2012
The 2012 metaanalysis: Thangaratinam S et al BMJ May 2012
Shoulder
dystocia
50 g reduksjon i fødselsvekt
Effect of a behavioural intervention in obese pregnant
women (the UPBEAT study): a multicentre,
randomised controlled trial.
Posten L et al Lancet Diabetes Endocrinol. 2015
Er effekten av intervensjon større ved fedme
(BMI > 30)?
BMI ≥ 30, Intervensjon (kost, fysisk, gnerelle helseråd)
mellom uke 15-18 fulle uker
Mean BMI
of 36·3,
(SD 4·8). 772parametre
randomly assigned
to standard
care
Ingen
effekt
på metabolske
(glukose,
insulinantenatal
og lipider)
and 783 were allocated the behavioural intervention
Men ca 0.5 kg mindre vektøkning i svangerskapet etter intervensjon
Gestational diabetes: No difference: 26% after standard care, versus
25% after the intervention, p=0·68).
Large for gestational age: No difference: 8% after standard care versus
9% after intervention, p=0·40.
Major obstetric haemorrhage: No difference (1% vs 3%).
Small-for-gestational-age (SGA, ≤5th customised birthweight centile:
No difference: 6% vs 5%
The effects of antenatal dietary and lifestyle advice for women who are
overweight or obese on neonatal health outcomes:
the LIMIT randomised trial
The effects of antenatal dietary and lifestyle advice for women who are
overweight or obese on neonatal health outcomes:
the LIMIT randomised trial
Jodie M Dodd et al BMJ and BMC Med, 2014
Jodie M Dodd et al BMJ and BMC Med, 2014
Study group: Overweight/obese (BMI≥ 25
kg/m2.
Secondary outcomes:
Primary outcomes:
Large for gestational age (LGA): No difference
Birth weight > 4500g: Lifestyle: 2.15% versus Standard Care 3.69%.
P = 0.04.
Birth weight above 4000 g : Lifestyle advice 15% versus standard care 19%
(p=0.04)
Adjusted risk ratio (aRR) = 0.59; 95% CI 0.36 to 0.98; number needed
to treat (NNT) = 66; 95% CI 34 to 950.
aRR 0.82, 0.68 to 0.99; number needed to treat (NNT) 28, 15 to 263; P=0.04
Respiratory distress syndrome: Lifestyle Advice 1.22% versus Standard
Care 2.57%. P = 0.02.
aRR = 0.47; 95% CI 0.24 to 0.90; NNT = 75; 95% CI 40 to 532.
Oppsummering av hvilke utfall som kan påvirkes av intervensjon i svangerskapet
(kost og fysisk aktivitet)
Svært kort oppsummering
I en generell fødepopulasjon.
1. Vektøkning ca 1.5‐2 kg. Effekten av kost tiltak synes størst.
Kost og annen livsstilsintervensjon i svangerskapet
Følgende må avente en ny metanalyse
2.Preeklampsi ? (Tangaratinam: Ca 30 % reduksjon I forkomsten?) 3.Gestasjonell diabetes? (Tangaratinam: Med diett : 60 % reduksjon) 4.Preterm fødsel? (Tangaratinam: Bare diett: 30 % reduksjon)
5.Fødselsvekt? (Tangaratinam: Sannsynligvis liten effekt )
6.Store barn ? (Tangaratinam:> 4000g eller LGA, Dodd>4000g)? 7.Skulderdystoci? (Tangaratinam: 60 % reduksjon)
7.Respiratory stress? (Dodd: færre ved intervensjon)
8.Andre utfall:
Sectio?: Sannsynligvis ingen effekt. Induksjon av fødsel: Sannsynligvis ingen effekt.
Dette leder til to spørsmål
1. Hvorfor synes effekten av å
intervenere i svangerskapet begrenset?
(dog ikke fraværende)
2. Hva er konsekvensen?
Dete er sikekrt vist at:
1.Gir en moderat reduksjon i vektøkningen (1-2 kg)
2. Andre?
Ny metananlyse kommer som kan endre denne listen
Fedme er mer enn BMI (kg/m2)!
Placenta
Systemic inflammatory
response
Cytokines
Endothelial
Insulin resistance/
activation
diabetes
Preeclampsia
Glucose
Insulin FFA
receptor
Tore Henriksen 2012
Placental
inflammatory
reaction
Increased fatty acid
transport?
Glucose transport?
BMI relaterte
METABOLSKE endringer
Dene matabolske og inflammatoriske Tilstanden fedme
er et resultat av (åre) lang endring I kroppen
Metabolske og
inflammatoriske endringer
• Overvekt og fedme medfører generelt i befolkningen en betydelig helserisiko.
Svangerskap er en motiverende periode for informasjon om og oppfølging
av overvekt og fedme.
Fedme
• Det er ingen holdepunkter for at råd om sunn kost og fysisk aktivitet hos
gravide gir uheldige svangerskapsutfall (aktive slankeprogrammer anbefales
ikke for gravide).
Normalvektig
15 år
Samlet vurdering av nytten av å intervenere hos gravide
med overvekt/fedme
for svangerskapsutfall
27 år
Svangerskap
• Ovenfor er dokumentasjonsnivået angitt for de viktige kliniske
utfall, som det finnes data for. Dokumentasjonen er i stor grad basert på nye
meta-analyser av randomiserte studier, som viser gunstige effekter,
særlig av kostråd, på noen utfall, men ikke alle.
• Den samlede vurderingen er at intervensjon med kost og tilpasset
fysisk aktivitet bør gis alle gravide og spesielt til dem med overvekt og fedme.
Prekonsepsjonell veiledning.
Anbefales, hvis praktisk mulig, for alle med BMI over 30:
Ved første svangerskapskontroll kartlegges:
Grundig anamnese, medisinsk og om livsstil.
Klinisk erfaring og fysiologisk kunnskap taler for at:
Redusert BMI,
Godt fysisk aktivitetsnivå
• En eller flere medfølgende sykdommer (co-morbiditet)* ?
• Familieanamnese
• Obstetrisk anamnese: tidligere preeklampsi, svangerskapsdiabetes,
tilveksthemning/placentasvikt, forløsning,
post partum blødning)
Råd: Som under svangerskapet, vanligvis med unntak av de spesielle tilskuddene.
Mål: Etterfølgelse av rådene om kost og mosjon, vektreduksjon
(5-10% eller mer), bedret fysisk kondisjon. (se også Helsedirektoratets hefte
”Gravid”. eller www.helsedirektoratet.no
• Blodprøver i tillegg til vanlige blodprøver:
Glukosebelastning?
Tyreoideastatus vurderes
Andre relevante blodprøver ved co-morbiditet
God kontroll på medfølgende sykdommer (co-morbiditet)
på konsepsjonstidspunktet spiller en viktig rolle for å redusere risikoen for
komplikasjoner.
Co-morbiditet:
• Diabetes/glukoseintoleranse (se Diabeteskapitlene)
• Hypertensjon
• Trombotiske sykdommer
• Autoimmune sykdommer (SLE, vaskulitter, nefropati)
• Maternell hjertesykdom,
• Meternell lungesykdom
• Fedmeopererte (bariatrisk kirurgi)
• Komplisert psykososiale anamnese
• Andre tilstander som kan gi økt risiko form svangerskaps og
fødselskomplikasjoner i kombinasjonen med fedme .
Kvinner med overvekt og fedme uten relevant komorbiditet:
Følges i primærhelsetjenesten hvis BMI er under 35.
Ved BMI over 30 legges en plan for en tettere oppfølging med kost og andre
livsstilsråd enn for gravide generelt.
Ved BMI over 35-40* (fedme klasse II og III) henvises kvinnen til spesialist ved
ca 24 ukers svangerskap, med oppfølging spesialist ved ca 32 og ca 36 uker.
Oppfølgingen ved ca 32 uker bør være ved aktuelle fødepoliklinikk for
planlegging av fødselen.
*Grensen må vurderes ut fra lokale forhold (samhandling med
primærhelsetjenesten, kapasitetsvurderinger og kompetanse).
Vektøkning i svangerskapet ved GDM:
Følger generelle retningslinjer
Institute of Medicine (IOM) retningslinjer:
Kvinner med relevant co-morbiditet
BMI
BMI
BMI
BMI
Aktuelle co-morbiditet vil avgjøre grad av oppfølging ved spesialist/fødepoliklinikk.
Ofte vil oppfølging i primærhelsetjenesten i samarbeid med spesialist
være det optimale.
(<20):
(20-25.9):
26-29:
>30:
12.5-18 kg
11.5-16 kg
7-11 kg
5-9 kg
Men:
Ved BMI 30-35 reduseres risikoen for noen uheldige svangerskapsutfall
(preeklampsi, makrosomi)
ved vektøkning 0-6 kg, kanskje litt økning av SGA
Kost og andre livsstilsråd vil generelt være som for adipøse uten co-morbiditet,
men tilpasset aktuelle pasient.
Også denne gruppen må sikres minst en konsultasjon (ca 32 uker) ved
aktuelle fødepoliklinikk for planlegging av fødselen.
Ved BMI over 35 forslås vektøkning på 0-5 kg. I praksi vil noen gå noe ned i vekt.
Det er akseptablet fortutsatt adekvat sammensatt kost og tilvekstkontroll
slik som anbefalt OBS: mangelen vektøkning kan bety placentasvikt,
derfor ultralydskontroll slik som anbefalt
Fødselen ved fedme (BMI<30).
Fødselen ved fedme
• Ved start av fødselen eller ved muligheten for akutt forløsning før fødselsstart
(f eks ikke-normalt CTG) legges to intravenøse tilganger.
Planlegging av fødselen er vesentlig for adipøse gravide. Konsultasjon ved
fødepoliklinikken ved ca 32 uker anbefales ved BMI >35, der også
anestesilege bør orienteres.
Induksjon:
Ved BMI under 35 følges de generelle indikasjonene for induksjon
(spesifikke medisinske indikasjoner og overtid).
Ved BMI over 35 med ukomplisert svangerskap tas pasienten inn til
vurdering for induksjon i løpet av den første uken etter termindato.
Tidspunktet for induksjon vurderes da individuelt.
Ved innleggelse i fødeavdelingen (alle fedmekategoriene)
bør anestesilege og vakthavende gynekolog orienteres.
• Tidlig epiduralkateter
vurderes, for eventuelt senere aktivering.
• Ved avvik i fødselsforløpet informeres
gynekolog og anestesilege.
• Fosterovervåkning.
Kontinuerlig CTG, eventuelt STAN, med tidlig amniotomi og skalpelektrode.
Ved bruk av ekstern CTG-registrering kan U2-proben være best.
Kontroll mot mors puls anbefales.
• Ved forløsning er det økt risiko for skulderdystoci både ved spontan og
instrumentell forløsning og beredskap for skulderdystoci anbefales.
• Operativ vaginal forløsning foreslås utført på operasjonsstue med
mulighet for godt forberedt omgjøring til sectio.
Helse og sykdom i et utvidet perspektiv
Sectio
• Regional anestesi der det er mulig
• Eventuell hengende buk kan trekkes opp med taping av abdomen, hvis det er tid.
• Hudsnitt: fortrinnsvis tverrsnitt
• Antibiotikaprofylakse: Anbefales både ved akutte og elektive keisersnitt.
• Post partum:
Økt risiko for post partum blødninger.
Risiko for infeksjon
Økt risiko for trombose.
Rask mobilisering og støttestrømper anbefales.
Lavmolekylært heparin
Alle med BMI over 40 foreslås gitt tromboseprofylakse uansett forløsningsmåte.
Preconception
al
Nutrition
Metabolic state
Infections
Alcohol/drugs
Stress
Pollution
Tore Henriksen 2011
Cardiovasc.
Diabetes
Mental health
Next
Etc
Generation(s)
Sunn livsstil kan aldri være usunt!
Takk !
21.01.13
Retningslinjer for svangerskapsomsorgen
Svangerskapsomsorgen i Norge
Faglige retningslinjer er i prinsippet anbefalinger og råd, og skal bygge på
god, oppdatert faglig kunnskap.
Retningslinjene er ment som et hjelpemiddel og er ikke direkte rettslig bindende for mottakerne
Fokus i svangerskapsomsorgen er flyttet fra kontroll til informasjon, råd og veiledning slik at den gravide i større grad kan ta ansvar for egen helse.
Svangerskapsomsorgen skal planlegges for denne helt spesielle kvinnen og hennes familie, i lys av seleksjon og risikovurderinger. •
•
”Formålet med svangerskapskontrollen er å sikre at svangerskap og fødsel forløper på en naturlig måte, slik at morens somatiske og psykiske helse, og hennes sosiale velvære, blir best mulig, sikre fosterets helse, slik at det kan fødes levedyktig og uten sykdom eller skade som kunne vært forhindret, oppdage og behandle sykdom og andre helsetruende forhold hos moren, slik at svangerskapet medfører minst mulig risiko for henne og barnet”. 180116 S Sand Oslogynekologene
1
•
•
180116 S Sand Oslogynekologene
Svangerskapskontrollen ‐ 1
•
•
•
•
•
•
Gravide kvinner er ikke syke, og de skal ikke sykeliggjøres
Gravide kan ha sykdom som kompliserer graviditeten
Gravide kan bli syke Den medisinske tryggheten må være GOD NOK
Perinatalkomiteens arbeid: en andel av perinatale dødsfall kunne vært unngått
Kvinnen selv er barnets beste og viktigste advokat
I noen få tilfeller er det nødvendig å beskytte barnet overfor mors livsførsel
Kartlegg den gravides behov
Sørg for kunnskapsbasert omsorg.
I byer og tettsteder er det et stort tilbud av alternative behandlere i svangerskapsomsorgen
180116 S Sand Oslogynekologene
3
Svangerskapskontrollen ‐ 2
1.Ressursfokus, mao hva er viktig å bruke tid på overfor denne pasienten
2.Skriftlig informasjonsmateriale? Av hva
3.Utfyllingen av helsekortet, hva er viktig og hvorfor
4.Organisering av kontrollene, hvordan vil du gjøre det, hvorfor, sykehist. 5.Utnytting av medarbeidere; BT/vekt/urin/evt CTG. Frigitt tid ‐ til hva?
6.Åpne for valg hos kvinnen (informasjon);
a. Fødested?
b. Spesielle behov, tidlig/sent/hele svangerskapet?
c. Prenatal diagnostikk? Uke 10‐14 (CVB, Duotest, AC) Alle henvises til gen.veil.
d. Behov for annen ”ekstern” ekspertise ( hematolog, kardiolog, etc)
e. ”Ønskebrev”???
180116 S Sand Oslogynekologene
Risikovurdering ut fra somatiske, psykiske og sosiale forhold
Tillit (ulike samlivsformer, ulike valg) skapes, det bestemmes ikke
Ukjente (for deg) problemstillinger? Søk råd! Alle kan ikke alt!! 1. Seksuelle overgrep?
2. Omskjæring? 3. Rusmisbruk?
4. Psykiske og fysiske funksjonsproblemer?
5. Kronisk sykdom?
6. Inaktivitet
7. Overvekt
2016
•
•
•
•
•
•
•
•
Hvor skal hva henvises? Skaff deg et repertoar av samarbeidspartnere •
180116 S Sand Oslogynekologene
5
s sand oslogynekologene
4
Helsekort for gravide
Svangerskapskontrollen ‐ 3
•
•
•
2
Dagens arbeidsredskap
Ofte manuelt utfylt; uoversiktlig
Inneholder nok informasjon?
Håndskrevet
Merknadsfelt: Bør brukes!
Medikamenter: Et lite felt
Liten plass for tiltak som skjer kontinuerlig i svangerskapet
ift effekt og utvikling Liten plass til vurdering av arb. situasjon, plan for barseltiden og lignende
Best egnet for de som trenger det minst?
180116 S Sand Oslogynekologene
6
21.01.13
Svangerskapskontrollen ‐ 4
Utføres mellom 11 og 12 kontroller i svangerskapet i Norge
•Jordmor
•Fastlege
•Praktiserende spesialist
•Sykehus poliklinikker
•Kombinasjon av en eller flere
Svangerskapskontrollen – 5
•
•
Ulike modeller for ”riktig” antall svangerskapskontroller
WHO : 4 rutinekontroller og en rutineultralyd hos lavrisikogravide vs 5‐7 kontroller
• Svangerskapshypertoni ved fødsel
• Preeklampsi ved fødsel
 Lav fødselsvekt (<2500g)
 Alvorlig anemi etter fødsel  Behandlingstrengende UVI
Bruker u.s.: De ulike aktørene utfyller hverandre med ulik kompetanse
Bruker ønske: Velge selv, helst gå i kombinasjon mellom lege og jordmor
180116 S Sand Oslogynekologene
7
Svangerskapskontrollen ‐ 6
•
Hvem utfører svangerskapskontrollene(lavrisiko)
• 16% kun til fastlegen
• 3% kun til jordmor
• Resten i kombinasjon fastlege/jm, fastlege/jm/spesialist, jm/spesialist, fastlege/spesialist
•
Kvinner med spesielle risikofaktorer henvises til høyere kompetansenivå i helsetjenesten
180116 S Sand Oslogynekologene
8
Svangerskapsomsorg hos spesialist utenfor sykehus ‐3
Dersom det foregående oppfylt:
• Stort potensiale for å flytte noe av svangerskapsomsorgen ut av sykehusenes fødepoliklinikker
• I dag er det mye dobbeltkontroller
• Vil frigjøre tid og resurser i sykehusavdelingene
Forutsetning:
• Seleksjon
• Tilgjengelige retningslinjer fra ”moder”‐ sykehuset • Samarbeidsmøter , ‐avtaler
• Avklart for hva og på hvilket tidspunkt pasienter henvises • Lett tilgjengelighet inn til sykehusavdelingen
Samhandling i praksis
180116 S Sand Oslogynekologene
9
Samhandling utenfor sykehus
•
•
180116 S Sand Oslogynekologene
10
Den nye SF kurven(rosa) sammenlignet med den gamle(grønne)
I mange fagdisipliner jobber kan man jobbe i sykehus og/eller avtalepraksis/privatpraksis når ferdig spesialist
Dagens spesialistutdanning er i stor grad forankret i problemstilling relatert til behandling i sykehus
Praktiserende spesialisters landsforening = PSL
Har arbeidet sammen med helsemyndighetene for at ½ år av spesialistutdanningen kan gjøres under veiledning i en avtalepraksis 2014 startet dette i urologi og hud
Enklere å ha samhandling mellom fastlegene og spesialisthelsetjenesten utenfor sykehus.
Sikret kontinuitet for pasienten bedre.
180116 S Sand Oslogynekologene
11
s sand oslogynekologene
180116 S Sand Oslogynekologene
12
21.01.13
Utsatte grupper i svangerskapsomsorgen
•
•
•
Kontrollene uke 24 ‐41
Psykososiale problemer
• Ernæring
• Alkoholmisbruk
• Stoff/medikamentmisbruk
• Vold og traumatisk stress
• Psykiatri
• Ingen nære rollemodeller
Innvandrergrupper (spes fra 3. verden)
• Lavt kunnskapsnivå, analfabetisme
• Dårlig egenomsorg
• FGM
• Dårlig nettverk
• Følger dårligere opp svangerskapskontrollene , misforståelser, fordommer begge veier
• Språkproblemer
Kost/ernæring
• Anorexi/bullemi
• Overvekt
180116 S Sand Oslogynekologene
13
180116 S Sand Oslogynekologene
Tiltak som ikke anbefales som en del av rutineundersøkelsene i svangerskapet: Diverse instanser
•
•
•
•
•
•
•
•
•
•
•
Nakmi , [email protected] ”Kommunikasjon via tolk” , Temahefte fra www.udi.no. ”Psykisk helse hos flyktninger”, Temahefte fra www.udi.no Arbeidstilsynets publikasjoner: e‐post: [email protected] Nasjonalt Folkehelseinstitutt : e‐post: [email protected] Statens forvaltningstjeneste : e‐post: [email protected] www.publikasjoner.dep.no Trykksakekspedisjonen Sosial‐ og helsedirektoratet : e‐post: [email protected] Støttesenter mot incest: 23 31 46 50: www.sentermotincest.no
Mental Helses Hjelpetelefon: 810 30 030 (døgnåpent): www.mentalhelse.no Organisasjonen Voksne for Barn: 23 10 06 10: www.vfb.no
Angstringen: 22 22 35 30: www.angstringen.no 180116 S Sand Oslogynekologene
15
Jm el fastl.
Spesialist
22
24
28
TVUL
TAUL
CTG
X
X
X
X
X
X
X
X
X
X
X
X
X
X
X
26
X
30
31
X
32
X
33
34
X
35
X
36
X
37
X
38
X
39
180116 S Sand Oslogynekologene
•
•
•
•
•
•
•
•
•
•
•
Hb‐måling hver gang Brystundersøkelse Gynekologisk undersøkelse Rutinemessig bruk av jerntilskudd Rutinemessig ferritin‐prøver av kvinner uten anemi
Screening for klamydia, CMV, Hep C, GBS, toksoplasmose Screening for prematur fødsel m/ cx vurdering: ved UL eller GU Telling av fosterbevegelser Rutinemessig CTG i svangerskap for kvinner med normalt svangerskap Rutinemessig UL etter 24 uker Rutinemessig dopplermåling av navlesnorsarterier for lavrisikogravide 180116 S Sand Oslogynekologene
Lavrisiko tvillingsvangerskap
Uke
X
17
s sand oslogynekologene
14
16