Ovulation & Human Fertilization

Ovulation is the event of de Graaf's follicles rupturing and releasing secondary oocyte ovarian cells. It is the phase of a female's menstrual cycle when an egg (ovule) is released from the ovaries.

After ovulation, during the luteal phase, the egg will be available to be fertilized by sperm. Concomitantly, the uterine lining (endometrium) is thickened to be able to receive a fertilized egg. If no conception occurs, the uterine lining as well as blood will be shed during menstruation.

Ovarian follicles are the basic units of female reproductive biology, each of which is composed of roughly spherical aggregations of cells found in the ovary. They contain a single oocyte (immature ovum or egg).

These structures are periodically initiated to grow and develop, culminating in ovulation of usually a single competent oocyte in humans. These eggs/ova are developed only once every menstrual cycle (e.g. once a month in humans), a woman begins puberty with about 400,000 follicles.