17. 14 ovarian function control: gnrh pulsatile secretion from hypothalamic neuroendocrine cells --> fsh & lh from anterior pituitary --> gonadal secretion estrogen & progesterone. Ovulation: levels of estrogen increase and cause surge in lh --> ovulation, + feedback: estrogen stimulating release of gonadotropin. 1-5: corpus luteum degeneration = low estrogen and progesterone, lead to shedding of endometrium lining. Increased fsh & lh secretion, stimulating follicle maturation. 7-12: single follicle becomes dominant, dominant follicle secretes estrogen --proliferation of endometrium, estrogen & inhibin negative feedback and decrease lh & fsh release, result in atresia of non-dominant follicles. Increasing estrogen [c] leads to lh surge: oocyte completes first meiotic division and matures, follicle secrete digestive enzymes & prostaglandins that mediate ovulation, ovulation. 15-25: formation of corpus luteum --secretes estrogen and progesterone, development of secretory endometrium. Inhibition of lh and fsh release from anterior pituitary: no new follicles develop. If no implantation, degeneration of corpus luteum: decrease in plasma estrogen & progesterone.