Explanation

Ovulation (release of egg or ovum from ovary into body cavity) involves the extrusion of a secondary oocyte from the ovary. Actually by 10-14 days after the first day of menstruation, only one follicle has contained its growth to become a fully mature Graafian follicle, while other follicles regress through a process called follicle atresia. Under proper hormonal stimulation, Graafian follicle rupture and extrude its oocyte into the uterine tube in the process of ovulation.