Puberty Flashcards
Adrenarche
Activation of adrenal cortex for the production of adrenal androgens, and typically occurs before the onset of puberty. Leads to pubarche (pubic and axillary hair growth) and doesn’t require gonads.
Gonadarche
Activation of the gonads by the pituitary hormones FSH and LH and sex steroid secretion. Leads to thelarche (breast dev) and sexual maturation. Does not require the adrenal gland
Menarche
Age of onset of first menstural period
Where is DHEAS produced?
During andrenarche, the adrenal gland’s zona reticularis produces DHEAS
Is adrenarche under direct control of ACTH/cortisol?
NO, has nothing to do with the gonads
What stimulates gonadarche
Onset of GnRH pulsitility
What usually comes first, thelarche or pubarche?
Thelarche, though in 8-15% of girls, pubarche occurs first
What causes breast dev?
Estrogen production by ovaries
Breast Tanner stage I
Prepubertal
Breast Tanner stage II
Breast bud forms, areola erect (11.2 y.o)
Breast Tanner stage III
Breast tissue enlarges beyond areola (12.2)
Breast Tanner stage IV
Areola and papilla form second mound (13.1y.o)
Breast Tanner stage V
Adult breast: areola and breast tissue same plane, papilla erect (15.3 y.o)
Limitations to Tanner staging
- Based off of limited pop
- Dif ethnicities=dif ages
(note seq of events is the same)
Normal breast dev occurs at a younger age in…
African Americans than in Whites
What age range of breast dev req further evaluation of any girl?
Dev at age 13
Which enzymes initiate adrenarche
P450c17 which inc DHEA, DHEA-s, androstenedione
How many years before the appearance of secondary sex charac does adrenarche occur?
2
What is adrenarche responsible for
Pubarche
Does andrenarche play a role in skeletal growth?
Not really
What is the relationship between adrenarche and gonadarche?
They are temporally related, but independent, functionally unrelated biologic events
F. Pubic Tanner stage I
Pre pubertal, no pubic hair