Illustration copyright 2000 by Nucleus
Communications, Inc. All rights reserved.
An ovarian cyst is a fluid-filled sac (follicle) that contains a
maturing egg. It forms on the ovary's surface, then disappears not long after
it releases the egg. If a mature egg is not released or if the sac reseals
after releasing the egg, the sac can swell up with fluid, forming a
functional ovarian cyst.
Most functional ovarian cysts do not cause symptoms and go away by
themselves. But they do sometimes rupture, twist, or bleed, which can
cause severe pelvic pain.
ByHealthwise Staff Primary Medical ReviewerSarah Marshall, MD - Family Medicine Martin J. Gabica, MD - Family Medicine Specialist Medical ReviewerKirtly Jones, MD - Obstetrics and Gynecology