ABSTRACT
The ovary in the female adult has a cyclic function that is both autonomous as well as directed by the hypothalamic-pituitary axis. The development of primordial follicles towards the antral stages and the elimination of the vast majority of these developing follicles along the way are fully under control of local factors. It is from the small antral stage of follicular development onwards that pituitary gonadotropin hormones facilitate the menstrual cycle. Dominant follicle growth, ovulation of the oocyte, and corpus luteum formation represent the key processes of the ovarian cycle and much is dependent on the interplay between pituitary gonadotropins, ovarian steroids, and peptides. The ultimate goal of the menstrual cycle is the implantation of a vital embryo in the endometrium that has been prepared under the influence of ovarian steroids.
