Sexual Development

Question 1

What is puberty?

Answer 1

Puberty” - begins with the earliest signs of sexual maturity and lasts until physical, mental and emotional maturation occur

Question 2

What is the onset of puberty in girls and boys?

Answer 2

GIRLS – average onset at 9, peak height velocity at 11.5 (range: 9.7-13.5)

BOYS - average onset at 11, peak height velocity at 13.5 (range: 11.7-15.3)

Question 3

how much adult height is accounted for in puberty? adult weight?

Answer 3

25% of final adult height is accounted for during pubertal growth

More than 40% of the ideal adult weight is accounted for during puberty

Question 4

What is the SMR?

Answer 4

The Sexual Maturity Rating (SMR) measures the stages of secondary sexual characteristics

• Also known as the Tanner Staging System
• Assigns a Tanner stage of 1 (prepubertal) to 5 (adult)
• For boys it is based on genitalia and pubic hair
• For girls it is based on breast development and pubic hair
• Completion takes approximately 4-5 years

Question 5

What does sexual development begin with in girls? in boys?

Answer 5

girls:
Begins with the growth of breast buds (thelarche) and pubic hair growth (pubarche)

boys:
First sign is scrotal corrugation and pigmentation, along with testicular enlargement

Question 6

when does the growth spurt happen in girls? boys?

Answer 6

girls = stage 3
boys = stage 4

Question 7

What are some normal variants of puberty?

Answer 7

1. breast asymmetry and masses
2. Physiologic Leukorrhea (clear discharge)
3. Irregular Menses
   Girls can have irregular periods for 2 to 5 years after the first menstrual period.
4. Gynecomastia (normal in adolescents and babies)

Question 8

What is precocious puberty?

Answer 8

Signs of puberty before age 8 in girls and before age 9 in boys

Question 9

What is delayed puberty?

Answer 9

Children who show no signs of puberty by age 13 (girls) or 14 (boys)

Question 10

What is bone age and how is it measured?

Answer 10

Skeletal maturity, or bone age, can be estimated from radiographs of the left hand and wrist.
From this radiograph, the bone age can be estimated and adult height can be predicted

calendar age
sex and
height
information about the parents

Question 11

What are the three main categories of pubertal delay?

Answer 11

Constitutional delay in growth
Hypogonadotropic hypogonadism
Hypergonadotropic hypogonadism

Question 12

What is the most common cause of delayed puberty?

Answer 12

Constitutional delay in growth

Question 13

describe Constitutional delay in growth

Answer 13

Normal variant!
Often have FHx of pubertal delay
Delayed bone age with no evidence of endocrinopathy or other organic disease
Diagnosis of EXCLUSION

Question 14

Describe Hypogonadotropic hypogonadism

Answer 14

aka CENTRAL HYPOGONADISM

Defect at the level of the hypothalamus or pitutiary
Results in deficient GnRH or gonadotropin secretion
Low basal LH and FSH
Absence of appropriate LH response to exogenous GnRH

Question 15

What are some causes of Hypogonadotropic Hypogonadism?

Answer 15

Kallman syndrome, problem with pit/hypothalamus, or systemic disease.

Question 16

Describe Hypergonadotropic Hypogonadism

Answer 16

aka PRIMARY hypogonadism

Defect at the level of the gonads
Serum concentrations of gonadotropins ( particularly FSH) elevated in children >10 yrs

Primary testicular failure:
Klinefelter’s syndrome (XXY)
XY gonadal dysgenesis
Anorchia
Cryptorchidism
Post chemotherapy or local irradiation

Question 17

What are some syndromes that are Hypergonadotropic Hypogonadism related?

Answer 17

Ovarian failure:
Turner syndrome (45XY or XO)
Testicular failure:
Klinefelter syndrome (47XXY)
Autoimmune disease

Question 18

What is the treatment for pubertal delay for constitutionally delayed adolescents?

Answer 18

In constitutionally delayed adolescents
Observation and reassurance is appropriate
In males, short-term hormonal therapy may be useful
Testosterone enanthate
No longer than 4-8 months

Question 19

How do you eval for pubertal delay?

Answer 19

1. recognize delayed puberty (>13 or >14)
2. get basal plasma gonadotropin levels (LH, FSH)
3. Is it high or low?
   If High…then hypergonadtropic hypogonadism (primary ovarian or testicular failure)…KARYOTYPE looking for turners or kleinfelters

If low or normal, the LH response to GnRH

• if no response = hypogonadtropic hypogonadisms or organic or functional cause
• if response then = constitutional delay aka normal variant

Question 20

Why does sexual precocity occur?

Answer 20

Results from an increase in circulating sex steroids

Question 21

what are two sources for sexual precocity?

Answer 21

Etiologic considerations may be divided into endogenous and exogenous sources:
1. Endogenous
Gonads, adrenal cortex

2. Exogenous
   Estrogen-containing creams, birth control pills, anabolic steroids, excessive fat tissue (fat makes estrogen)

Question 22

who is sexual precocity more common in?

Answer 22

girls

Question 23

What causes sexual precocity in girls?

Answer 23

Central precocity :
Often idiopathic
Can be due to CNS abnormalities

Primary or peripheral precocity:
Ovarian abnormalities
Adrenal hyperplasia

Question 24

What are the causes of sexual precocity in boys?

Answer 24

Much less common

Peripheral and central are equally common

The younger the child with precocity, the higher the likelihood of CNS abnormality

Question 25

What are two causes of primary precocity in boys?

Answer 25

McCune Albright Syndrome
Genetic mutation causing hypersecretion of hormones

Leydig cell hyperplasia
Genetic mutation causing testicular production of testosterone without LH stimulation (testotoxicosis)

Question 26

What is the workup for precocious puberty?

Answer 26

Extensive hormonal workup is needed to evaluate cause of precocity in both boys and girls
-GnRH, FSH, LH, Estrogen, Progesterone (females)
-GnRH, FSH, LH, Testosterone (boys)
Bone Age (X-ray of Left Wrist)
Endocrine Referral
Treatment targeted at specific etiology and varies widely
Usually managed by Endocrine

Question 27

does menarche occur early or late in puberty? what is the mean age for menarche? what does it signify?

Answer 27

late
12.8
closure of the epiphyseal plates