Control of ovarian function by hypothalamus
Trough GnRH (gonadotropin-releasing hormone) secreted in episodic bursts
_ estrogens, _ progesterone : _ frequency of GnRH
early follicular phase - FSH secretion, stimulation of follicle growth, LH inhibited by negative feedback
estrogens: _ frequency of GnRH
late follicular phase with LH culmination - before ovulation
progesterone, testosterone: _ frequency of GnRH