Function: The ovaries contain and nurture the female's lifetime complement of ova. Feminizing features of puberty result from estrogen produced by the granulosa cells, and androgen hormones from the medulla. The thecal cells produce androstenedione used as a precusor for estrogen production. Directed by estrogen, the hypophysis secretes gonadotrophins that cause cyclic follicle maturation and ovulation of an ovum by the predominant follicle. Ova fall freely into the peritoneal sac in the region of the fimbria of the uterine tube, or into the rectouterine pouch.The corpus luteum produces progesterone for creating a secretory endometrium in the uterus. If conception occurs, this organelle becomes the corpus luteum of pregnancy that maintains the pregnancy for 8-10 weeks, until the placenta 'takes over'.