Ovarian cyst

An ovarian cyst is any collection of fluid within the ovary. Some of these, called functional cysts, are part of the normal process of menstruation. Any ovarian follicle that is larger than about 2 centimeters is termed an ovarian cyst: specific types of cyst include graafian follicles (which may rupture at mid-cycle and cause mittelschmerz) or corpus luteum cysts (which may rupture about the time of menstruation, and take up to three months to disappear entirely).

Other cysts are pathological, such as those found in polycystic ovary syndrome, or those associated with tumors.

The vast preponderance of ovarian cysts in women of pre-menopausal age are benign; those occurring in post-menopausal women may indicate more serious disease and should be investigated through ultrasonography, especially in cases where other family members have had ovarian cancer. Such cysts may require surgical biopsy.