The oocide is found inside the follicle. So the primary follicle becomes a secondary follicle. In the process we produce estrogen. And the estrogen, what it does is it begins the thickening of the lining of the uterus. It initiates the thickening of the endometrium that is needed for implantation to actually take place. So eventually when you form the mature secondary follicle, ovulation takes place and that follicle ruptures, releasing that secondary oocide, the xcel, into the pericneal cavity.