Clinical assessment of sexual maturation in adolescents

Jornal de Pediatria - Vol. 77, Supl.2 , 2001 S135
0021-7557/01/77-Supl.2/S135
Jornal de Pediatria
Copyright © 2001 by Sociedade Brasileira de Pediatria
REVIEW ARTICLE
Clinical assessment of sexual maturation in adolescents
Eugenio Chipkevitch*
Abstract
Objective: to present the methods for clinical evaluation of sexual maturation in adolescents.
Methods: bibliographic review concerning the practice of pubertal staging.
Results: the assessment of sexual maturation is an essential step in the comprehensive health care of
adolescents, allowing for the evaluation of their developmental stage. In addition, this assessment allows
establishing a correlation between different pubertal events, following up diseases, and interpreting
laboratory tests appropriately. Pubertal stage is assessed by the examination of breasts and pubic hair in
females, and genitals and pubic hair in males. A new photographic standard for pubertal staging and a new
method for clinical measurement of testicular volume are presented.
Conclusions: the assessment of sexual maturation is an important feature in the health care of
adolescent patients and must be included in the clinical practice of pediatricians involved in adolescent
medicine.
J Pediatr (Rio J) 2001; 77 (Supl. 2): S135-S142: adolescence, puberty, sex maturation.
Introduction
Puberty is a period of biological maturation marked by
the appearance of secondary sexual characteristics, growth
spurt, and changes in body composition. With the exception
of the fetal period, there is no other stage in human
development in which height growth and changes in body
composition are as intense and rapid as during puberty. The
growth spurt, for example, lasts three to four years and
represents approximately a 20% and 50% gain in relation to
adult height and weight, respectively.1
In adolescence, chronological age is not a reliable
parameter for biological, psychological, and social
characterization of individuals. Adolescents with the same
age are frequently in different stages of puberty considering
that its onset and progression are highly variable. Most
pubertal events (maximum growth velocity, menarche, final
height, and so on) and most pathologies associated to
puberty (acne, scoliosis, gynecomasty, and so on) are more
often correlated to specific stages of puberty than to
chronological age.1 Pubertal staging allows doctors to
assess the maturation of adolescent patients; to correlate
several pubertal phenomena; to estimate age at menarche,
growth spurt, and final height; to offer early orientation to
youngsters in relation to upcoming pubertal events; to offer
* Director of the Paulista Institute for Adolescence, former director of the
Adolescent services of the Children’s Hospital Darcy Vargas, São Paulo.
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S136 Jornal de Pediatria - Vol. 77, Supl.2, 2001
advice on choice of proper sports modalities; to assess
exams properly; and to treat pathologies associated to
puberty.1
In this sense, pubertal staging is an important measure
for characterizing the maturation of adolescents and for
easier understanding and handling of the most common
clinical problems for this age group. Our objective is to
offer a brief review on the practice of pubertal staging, and
to present a new photographic model on the stages of sexual
maturation and a new method for measurement of testicular
volume.
Pubertal staging
Though certain models of pubertal staging had already
been proposed during the 1940s and 1950s,2-4 doctor J.M.
Tanner was the one who presented a standardized method
for staging of sexual maturation,5 which became widely
used during the 1960s and is still the most widely used
method.
Staging of sexual maturation is carried out with breast
and pubic hair growth examination for girls, and with
genital and pubic hair growth for boys. Breasts and genitals
are examined according to size, shape, and characteristics
and pubic hair according to quantity and distribution (Table
1). Stage 1 (Tanner 1) corresponds to the prepubertal phase
and stage 5 (Tanner 5) corresponds to late-pubertal (adult)
phase. In this sense, stages 2, 3, and 4, or the midpubertal
stages, represent puberty. Stages 2 to 4 are conventionally
called sexual maturation stages, or Tanner stages.
The classical work of Tanner included a set of blackand-white photographs for illustration of each maturation
stage for both sexes.5 A few years later, a Dutch group
published a set of color photographs for these same stages.6
In this article, we reproduce our black-and-white model for
sexual maturation (Figures 1, 2, 3, and 4) originally published
in 1995.1 This is the first published Brazilian model and the
third in the international literature.
For each sex, staging is carried out according to two
steps: breasts (B) and pubic hair (P) growth for girls, and
genitals (G) and pubic hair (P) for boys (Table 1). It is
recommended to always assess these two steps separately;
for example, B3P3 instead of stage 3. Adolescents may be
in different maturation stages for each of the two
characteristics, for example, B4P5 or G2P1 considering
that maturation of the characteristics depends on different
hormonal and genetic mechanisms. Pubertal events correlate
differently to specific components of maturation staging;
for example, age at menarche is more correlated to breast
development than to pubic hair growth. Most adolescents
do not present differences of more than one stage between
B and G in relation to P; however, situations of G1P3,
G4P1, or M3P1, though rare, can be observed in normal
adolescents. Nevertheless, important differences as such
can also be an indication of a pathology (supra-renal,
testicular, etc).7
Clinical assessment of sexual maturation... - Chipkevitch E
Table 1 -
Sexual maturity rating
Male genitals
G1
Childlike penis, testicles, and scrotum.
G2
Initial increase in testicular volume (>4ml). The
texture of the scrotal skin becomes reddened
and thinner. The enlargement of the penis is
minimal or absent.
G3
Increased length of the penis. Great enlargement
of testicles and scrotum.
G4
Increased length and circumference of the penis
with great enlargement of the glans. Enlarged
testicles and scrotum, and increased scrotal skin
pigmentation.
G5
Full development of genital organs, with adult
appearance.
Breasts (females)
M1
Childlike, with elevated papilla.
M2
Breast bud: initial increase of the mammary
gland, with elevated areola and papilla, forming
a small mound. Areolar diameter and texture
change.
M3
Great enlargement of the breasts and areola,
without contour separation.
M4
Greater enlargement of the breast and areola. A
second mound is formed above the breast
contour.
M5
Adult mature breasts. Recession of areola to the
mound of breast tissue.
Pubic hair (both sexes)
P1
No pubic hair. Vellus over the pubes in no
further developed than that over the abdominal
wall.
P2
There is sparse growth of long, slightly
pigmented, downy hair, straight or only slightly
curled, appearing chiefly at base of penis or
along the labia majora).
P3
Hair is considerably darker, coarser, and more
curled, and spreads sparsely over junction of
pubes.
P4
Hair is now adult in type but there is no spread
to the inner thighs.
P5
Adult quantity and distribution with hair present
on inner thighs.
P6
Hair spreads above the pubes.
During puberty, there is an increment in nipple (papilla)
and nipple areola in both girls and boys, but especially in the
earlier. The increment in nipple diameter is greater during
stages B4 and B5, which helps to differentiate stages B3,
Clinical assessment of sexual maturation... - Chipkevitch E
Figure 1 - Stages of sexual maturation in males - genitals
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Clinical assessment of sexual maturation... - Chipkevitch E
Figure 2 - Stages of sexual maturation in males - pubic hair
Clinical assessment of sexual maturation... - Chipkevitch E
Figure 3 - Stages of sexual maturation in females - breasts
Jornal de Pediatria - Vol. 77, Supl.2 , 2001 S139
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Figure 4 - Stages of sexual maturation in females - pubic hair
Clinical assessment of sexual maturation... - Chipkevitch E
Clinical assessment of sexual maturation... - Chipkevitch E
Jornal de Pediatria - Vol. 77, Supl.2 , 2001 S141
B4, and B5. The nipple presents little increase between
stages 1 and 3 and marked increase between stages B3 and
B4 (diameter averages of 3 mm for B1; 3.4 mm for B2; 4.7
mm for B3; 7.3 mm for B4; and 9.4 mm for B5).7,8
Initially, the appearance of thelarche (B2) may occur in
only one breast; the contralateral breast will usually start
growing weeks or months later. Breast asymmetries,
however, can persist for some time between B2 and B4 or,
in some women, be permanent. The stage B4 is not observed
in all girls; apparently, some female individuals go directly
from B3 to B5 or stage B4 occurs so rapidly that it is not
registered in successive medical appointments. Conversely,
in other girls breast development may stop in stage B4.
The stage 6 of pubic hair growth is observed in
approximately 80% of men and 10% of women; in certain
individuals, it will only be complete years after puberty is
over.
Testicular volume
The measurement of testicular volume represents an
additional instrument for assessment of male sexual
maturation.
The most widely used method for measuring testicular
volume uses the Prader orchidometer, which includes 12
ellipsoid testicular models made of wood or plastic and
attached to a string. The models have volumes of one to 25
ml.9 To assess testicular volume, the doctor palpates the
testis with one hand while holding the orchidometer in the
other, examining the patient for the model that is more
similar to the palpated testis.
Takihara et al.10 proposed a new orchidometer that
consists of a graded series of punched-out elliptical rings
with the volume of the ellipsoids indicated on each ring for
volumes of 1 to 30 ml.
Considering that orchidometers are not easily available
in our setting, other methods that offer similar precision can
be applied. Thus, it is also possible to measure the two axes
of the testis with a transparent ruler or, better yet, with a
caliper (similar to that used for measurement of skinfold)
and calculate the volume using the formula V = 0.523 x L
x C2 (with V for volume, L for longitudinal diameter, and C
for cross-sectional diameter).
The measurement of testicular volume by
ultrasonography employs the same principle, though it has
been reported as the most precise method.11 We were able
to show, in a different article, that all methods offer
comparable reliability as long as the volumes obtained are
corrected using the equations of the linear structural model.12
In this sense, it was possible to propose a method for visual
comparison of the palpated testes with graphic models for
estimation of testicular volume (Figure 5); this new proposed
method is, thus, simple and its reliability comparable to that
of orchidometer and ultrasonography.12
Figure 5 - Scheme for graphic measurement of testicular
volume. The testicle is palpated and visually
compared with the graphic models. Testicular volume
is determined according to one of the six volumes or
one of the intermediate volumes between two
consecutive volumes depicted . The entire
measurement scale includes 13 volumes: less than
2ml, 2ml, 3.5ml, 5ml, 7.5ml, 10ml, 12.5ml, 15ml,
17.5ml, 20ml, 22.5ml, 25ml, and greater than 25ml
In general, the testes of children have one to two, and
sometimes three, ml in volume. Testes with four ml or more
are, almost as a rule, characteristic of puberty. Consequently,
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attaining a volume of four ml or more is an indication of G2;
this is an example of how measurement of testicular volume
can help to carry out pubertal staging. A testicular volume
of three ml is generally prognostic of puberty, for an
estimated 80% chance of starting within the following six
months.7 Eleven to 12-year old boys with small testes (one
to two ml) are probably affected by delay of pubertal
development (usually constitutional).
Measuring testicular volume is also important for the
assessment of diagnosis of certain pathologies; for example,
cases of Klinefelter syndrome (small testes) or of FragileX syndrome (possible macro-orchidism). The follow-up
measurement of testicular volume is important in postsurgical
follow-up of orchipexy (to check whether ectopy, twisting
and/or surgical handling has affected testicular development)
or of varicocele (that presents risk for testicular hypertrophy
and subfertility).
Most adolescents have similar left- and right-hand side
testicular volumes; however, it is common for the left-hand
side testicle to have a slightly lower volume than the righthand side one. In cases of significant differences (20%), it
is important to examine the patient for factors that may be
interfering in growth of the smaller testis (varicocele,
previous surgery, orchitis, twisting, etc).
Testicular volume is significantly correlated with the
testicular function. Some authors consider a testicular volume
of 12 ml, attained, in average, around 13 to 14 years of age
and during maximum growth velocity, the minimum volume
compatible with fertility; in this sense, attainment of this
volume is comparable to menarche as a reference for male
sexual maturity.1
The average testicular volume of Brazilian adolescents
is four ml for G2, nine ml for G3, 16 ml for G4, and 20 ml
for G5. However, there can be significant variations in these
values. Consequently, a specific testicular volume cannot
be used to define stage of sexual maturation. Adult testes,
for example, can vary from 12 to 30 ml in volume.7
References
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clínicos e psicossociais. São Paulo: Roca; 1995.
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2. Schonfeld WA. Primary and secondary sexual characteristics:
Study of their development in males from birth to maturity, with
biometric study of penis and testes. Am J Dis Child 1943; 65:
535-49.
3. Reynolds EL, Wines JV. Individual differences in physical
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4. Reynolds EL, Wines JV. Individual differences in physical
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9. Prader A. Testicular size: Assessment and clinical importance.
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orchidometer and its clinical application. Fertil Steril 1983; 39:
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11. Behre HM, Nashan D, Nieschlag E. Objective measurement of
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Correspondence:
Dr. Eugenio Chipkevitch
Instituto Paulista de Adolescência
Rua Alcides Ricardini Neves, 12 - cjs. 906-909
CEP 04575-050 – São Paulo, SP, Brazil
Phone/fax: + 55 11 5506.9005
E-mail: [email protected]