Week 3 - Puberty and Abnormalities of Menstruation

Question 1

State the range of ages for thelarche (breast enlargement).

Answer 1

8-11 years

Question 2

State the range of ages for adrenarche (pubic hair) in females.

Answer 2

11-12 years

Question 3

State the range of ages for the growth spurt in females.

Answer 3

10-14 years

Question 4

State the range of ages for menarche in females.

Answer 4

11-15 years

Question 5

What is precocious puberty in females?

Answer 5

Precocious puberty is defined as the presence of physical signs of sexual maturation before 8 years old or menarche before 10 years old.

Question 6

What can true precocious puberty be caused by?

Answer 6

Premature secretion of gonadotrophins:

1. Idiopathic
2. CNS lesions - e.g. hypothalamic tumours, post-encephalitis neurofibromas

Question 7

How may meningitis cause precocious puberty?

Answer 7

Irritation and inflammation such as meningitis can cause early rises in GnRH secretion

Question 8

What is primary amenorrhoea?

Answer 8

Failure to menstruate by the age of 16 years (frequently because of delayed puberty)

Question 9

What external genitalia will XY individuals with androgen insensitivity syndrome have? What internal genitalia will they have?

Answer 9

External female genitalia because their tissues do not respond to androgen
Their male gonad will produce MIH so they will not have internal female ducts and will present with primary amenorrhoea

Question 10

What is the possible explanation for primary amenorrhoea in the context of low FSH and LH levels?

Answer 10

Problem is likely of pituitary or hypothalamic origin:

1. Pituitary tumours
2. Anorexia nervosa, malnutrition or psychogenic causes can also lead to hypogonadotropic hypogonadism
3. Check serum prolactin and consider imaging for a cranial lesion

Question 11

What proportion of normal 14 year old males would be expected not yet to be exhibiting signs of puberty?

Answer 11

The proportion would be very low (3-5%), since puberty in boys visibly begins between 9-14 years of age with scrotum and testicular development, however full maturity may not be completed until early 20s (e.g. facial hair)

Question 12

How can bone age be determined?

Answer 12

Bone age can be determined by hand-wrist films and compared with standards for the patient’s chronologic age

Question 13

How do you assess where a boy is in his pubertal growth spurt?

Answer 13

The growth spurt for boys is approximately 10 cm/year so height comparisons over time are useful