The ovarian cycle occurs in women from puberty to menopause. It's the set of periodic modifications and actions of the ovaries. During this period estrogen and progesterone, the female hormones, are released.

We say follicle to a cell formed by a oocyte and a follicle cell. They produce estrogen and whith this hormones they can increase the walls of the uterus. Then it begans Graaf's Follicle and the walls of the uterus are hardened.

After this, the Graaf's Follicle release the oocyte and it could be fertilized. The remaining cells are named corpus luteum which is responsible for the release of progesterone.