Single Best Answer (SBA) · Differences of Sex Development
Which endocrine change is responsible for initiating pubic hair growth in puberty?
Show answer and explanation
Answer: E. Production of adrenal androgens (androstenedione and dehydroepiandrosterone)
Endocrine changes of puberty
Puberty is driven by a higher-amplitude pulsatile release of LHRH (GnRH), with gradual increases in FSH, LH and oestradiol.
Key changes
- FSH and LH peak at menarche; pulsatile LHRH drives the axis.
- Rising oestradiol stimulates breast and uterine growth (and activation of the basal endometrium).
- Androstenedione and dehydroepiandrosterone (adrenal androgens) production is responsible for the initiation of pubic hair growth (adrenarche), paralleling it.
Why E
Adrenal androgens (androstenedione, DHEA) initiate pubic hair growth.
Why the others are wrong
A fall in oestradiol, FSH or adrenal androgens, or an MIF surge, do not initiate pubic hair - it is the rise in adrenal androgens that does.
Practise every Obstetrics & Gynaecology topic
This is a free sample. Sign up for the full bank of flashcards and exam-style questions on a spaced-repetition schedule, with 20 free stars a day.
More on Differences of Sex Development
- FlashcardWhat are primary and secondary sexual characteristics?
- True/False MCQRegarding androgen insensitivity syndrome, which of the following statements are TRUE?
- FlashcardWhat is the normal sequence of pubertal development in boys?
- SBA questionA girl has had no breast development by the age of 13 years. Which condition should be suspected?