Clinical_Rounds_in_Endocrinology_Volume_II_-_Pediatric_Endocrinology

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5. What is the sequence of normal pubertal development in females?

Normal pubertal development is characterized by a predictable, progressive

sequence of events which occur after reactivation of HPG-axis. The normative

data for the sequence of events of pubertal development is derived from the

landmark studies by Tanner and Marshall in 1960s. In girls, the first sign of

puberty is increase in height velocity, closely followed by thelarche. However,

in clinical practice, thelarche is regarded as the first sign of puberty as it is eas-

ily appreciable. Thelarche is followed by pubarche and menarche. The mean

time interval between the onset of breast budding to the development of adult

breast is 4.4 ± 2 years, and the mean interval between breast budding to men-

arche is 2.3 ± 1 years. In majority of girls, menarche occurs at Tanner breast

stage B 4 and the peak height velocity at B 3. The mean age of onset of pubertal

events in females as described by Tanner and Marshall are summarized in the

table given below.

Pubertal events

Mean age at onset in years

(range)

Mean age at completion in years

(range)

Initiation of height spurt 10.5 14

Thelarche 11.15 (8–13) 15.33 (13–18)

Pubarche 11.69 14.41

Menarche 13.47 (10–16.5) –

Peak height velocity 12.14 (9.5–14.5) –

6. What is the sequence of normal pubertal development in males?

The first sign of puberty in boys is the enlargement of testes, followed by pubarche

and penile enlargement. Testicular and penile growth is accompanied with pro-

gressive enlargement of scrotum along with increasing pigmentation and rugosity

of scrotal skin. The growth spurt starts along with penile enlargement and the

peak height velocity occurs during Tanner genital stage G 4 (at a testicular volume

10 ml) and pubic hair stage P 4. The mean time interval between the onset of tes-

ticular enlargement and penile enlargement is approximately 1 year, and develop-

ment of pubic hair to stage P 5 marks the completion of puberty in boys. The mean

age of onset of pubertal events in boys as described by Tanner and Marshall is

summarized in the table given below.

Pubertal events

Mean age at onset in years

(range)

Mean age at completion in years

(range)

Testicular enlargement 11.4 (9.5–13.5) 15 (13.5–17)

Genital staging G 2 at 11.5 G 5 at 15

Pubarche 12 16

Initiation of height spurt 12.5 (10.5–16) 16 (13.5–17.5)

Penile enlargement 12.5 (10.5–14.5) 14.5 (12.5–16.5)

Peak height spurt 14 –

6 Precocious Puberty