Physical Growth and Development In Adolescents
Warren M. Seigel M.D., F.A.A.P., F.S.A.M.
Chairman, Department of Pediatrics
Director of Adolescent Medicine
Coney Island Hospital
Brooklyn, NY
Associate Professor of Clinical Pediatrics
State University of New York at Brooklyn
I.
Normal Growth and Development
A.
Puberty – the physical changes associated with development
1. Major changes during puberty
 Maturation of primary sex organs and the
appearance of secondary sexual characteristics
(e.g. pubic hair, facial hair)
 Skeletal growth increases
 Body composition and distribution of fat
becomes more adult like
 Strength and endurance increases
2. Features of Puberty
 Sequence of changes is similar for all adolescents
 Variations in tempo or timing are common among
adolescents
 Physical changes reflect underlying hormonal
change.
II.
Pubertal Development
General Concept – sexual maturity rating (also known as Tanner
Staging) – a shorthand notation used to describe stages of physical
development
A.
Female
1. Typical sequence of events
 Thelarche – breast development
 Adrenarche – pubic hair development
 Pubarche – growth
 Menarche – appearance of menses
B.
Breast Development
 SMR-1:
the typical preadolescent breast.
Lacking breast tissue or significant development of
the nipple or areola
 SMR-2:
the breast and papilla become
elevated and appear as a small mound. There is
increased areolar diameter as well as the
appearance of increased areolar pigmentation
 SMR-3:
the breast and areola are enlarged but
are continuous in contour, with separation of the
nipple from the contour of the breast
 SMR-4:
the breast and areola continue to
increase in size and mass. There is separation of
the areola and papilla of the nipple to form a
separate mound of tissue
 SMR-5:
the mature female breast. The nipple
projects slightly but the areola is contiguous with
the contour of the breast
C.
Pubic Hair
 SMR-1:
preadolescent
 SMR-2:
sparse, downy, straight pubic hair
appears first at the medial border of the labia
majora.
 SMR-3:
darker, curly pubic hair, appears at the
medical aspect of the labia majora and spreads
upward and outward in a typical triangular
distribution
 SMR-4:
coarse, curly pubic hair becomes
more abundant, but less than typical adult amount
and distribution
 SMR-5:
coarse, curly pubic hair, in typical
adult female distribution with pubic hair present on
the medial aspects of the thighs or coursing
upwards along linea alba up toward the umbilicus
D.
III.
Important Features of Adolescent Female Development
1. Average age of onset of puberty = 10 years (range 813).
2. Growth spurt (peak height velocity) occurs during
SMR-2.
3. Average height achieved during growth spurt = 4-6
inches.
4. Rate of growth in females decreases immediately prior
to the onset of menses.
5. Menarche (onset of menses) occurs during SMR-4 in
the majority of females (May be delayed to SMR-5
occasionally).
6. Average age at menarche = 12 years (range 10-16)
7. At menarche, the majority of females have achieved
95% of their ultimate adult height.
8. Length of puberty = 4 years
 Pubertal development may be delayed by poor
health, intense exercise, low body weight, poor
nutrition, chronic illness.
9. Breast asymmetry is common in adolescent females and
does not signify pathology.
10.Acne often accompanies pubertal development and may
become severe during SMR stages 3 and 4.
PUBERTAL DEVELOPMENT IN ADOLESCENT MALES
A.
Sequence of pubertal changes in males
 Enlargement of the testes
 Lengthening of penis
 Appearance of pubic hair
 Physical growth
 Sexual maturity rating (also known as Tanner
stage) are utilized in the assessment of adequacy of
males development
B.
Testicular development
 SMR-1:
preadolescent testes
 SMR-2:
testicles slightly enlarged, scrotal skin
darkens in pigment, texture thins
 SMR-3:
testicles increase in size and volume
 SMR-4:
testicles increase in size, scrotal skin
dark
 SMR-5:
adult tests and scrotum
C.
Penis development
 SMR-1:
preadolescent male
 SMR-2:
darkening of site of circumcision (in
circumcised males), slight increase in length
 SMR-3:
enlargement of the glans penis and
increase in length
 SMR-4:
larger, glans and breadth increases in
size
 SMR-5:
adult penis
D.
Pubic hair development
 SMR-1:
preadolescent; no pubic hair
 SMR-2:
sparse, downy straight pubic hair
located at the base of the pubic bone and base of
the penis
 SMR-3:
coarse, darker pubic hair initially
located at the base of the penis and extending in an
upward, outward direction
 SMR-4:
darker, curly pubic hair increased in
amount, in similar distribution to stage 3 but less
amount than in the adult
 SMR-5:
adult masculine pubic hair
distribution to include pubic hair present at medial
aspects of the thighs. May not hair coursing
upwards alone linea alba toward the umbilicus
E.
Important features of male pubertal development
 Average age of onset of puberty = 12 years (range
9-13)
 Growth spurt (peak height velocity) occurs
generally between SMR-3 and SMR-4
 First ejaculation occur at SMR-3

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F.
Sperm production (spermarche) occurs at SMR-3
Average height gained during puberty = 5-7 inches
Strength peak occurs between SMR-4 and SMR-5
Gynecomastia (swelling of breast tissue) very
common among adolescent males; occurs in
approximately 60% of boys between SMR-2 and
SMR-4
Common concerns about puberty in adolescents
 Pubertal delay – often perceived delay by the
adolescent, but within normal range
 Puberty beginning early – more common in
females (may result in stress), but generally normal
variation
 Partial puberty beginning early
 Premature thelarche – isolated breast development
 Premature adrenarche – isolated pubic hair
development
 Neither premature adrenarche or thelarche indicate
significant pathology or endocrine abnormality.
Must be placed within the context of the patient
and his/her history and physical examination.
G.
Other physical or laboratory findings associated with
pubertal change in adolescents
 Serum alkaline phosphatase levels rise for both
males and females during periods of rapid growth.
Elevated levels will decrease following period of
significant growth.
 Hemoglobin and hematocrit will increase under
hormonal influence during period of growth.
Increase will be sustained following pubertal
change.