Proliferative Phase

b. Proliferative phase / Follicular phase / Post menstrual phase : This is the period between the end of menstruation and ovulation (the release of the ovum); its duration is more variable than the other phases, generally extending from about day 5 to day 13 of the cycle. During this phase, a small group of secondary follicles (about 6–12) begin developing further, but normally only one of them matures into a Graafian (mature) follicle, while the remaining secondary follicles degenerate in the same process of atresia mentioned earlier. The stimulus for the proliferation of new follicles comes from gonadotropin-releasing hormone (GnRH), secreted by the hypothalamus, which in turn stimulates the release of follicle-stimulating hormone (FSH). …