Table of Contents
Definition of Ovulation Cycle
The maturation and release of an ovum (egg) during a woman’s monthly menstrual cycle.
Ovulation establishes fertility (the physiologic ability to conceive a pregnancy); only during ovulation may pregnancy occur. Ovulation marks the transition from the proliferative phase to the luteal phase of the menstrual cycle, during which the pituitary gland’s release of luteinizing hormone (lh) stimulates the ovarian follicle (sometimes called the graafian follicle) to rupture.
The follicle expels the ripened ovum into a small pool of fluid that surrounds the ovary. The fimbriae (fluted edges of the fallopian tube) float in this fluid. As the fimbriae undulate they draw the ovum toward them and into the fallopian tube, where contractions of the tube’s wall propel the ovum along the fallopian tube toward the uterus. Fertilization, if it is to occur, takes place in the fallopian tube.
It is very difficult to calculate or determine the timing of ovulation. Though ovulation generally occurs within 10 to 15 days after the start of the previous menstrual period, its timing depends on numerous factors, most of which are hormonal. Body temperature rises slightly and the quality of cervical mucous changes during ovulation.
Home ovulation testing kits can determine ovulation with fair accuracy; laboratory tests done through the doctor’s office are more precise. Ovulation timing is important for women who are trying to conceive, and also for women who are trying to avoid conception.
For further discussion of ovulation within the context of the structures and functions of reproduction and sexuality, please see the overview section “The Reproductive System.”
Page last reviewed: