A Member of the University of Maryland Medical System | In Partnership with the University of Maryland School of Medicine

Get answers to your Urinary Incontinence / Urogynecology questions.
Dr. Johnson’s Bio | Q&A Archive
Physiologic ovarian cysts; Functional ovarian cysts; Corpus luteum cysts; Follicular cysts
An ovarian cyst is a sac filled with fluid that forms on or inside of an ovary.
This article is about cysts that form during your monthly menstrual cycle, called functional cysts. Functional cysts are not the same as cysts caused by cancer or other diseases.
For more information about other causes of cysts on or near the ovaries, see also:
Each month during your menstrual cycle, a follicle (where the egg is developing) grows on your ovary. Most months, an egg is released from this follicle (called ovulation). If the follicle fails to break open and release an egg, the fluid stays in the follicle and forms a cyst.This is called a follicular cyst.
Another type of cyst, called a corpus luteum cyst, occurs after an egg has been released from a follicle. These often contain a small amount of blood.
Ovarian cysts are somewhat common, and are more common during a woman's childbearing years (from puberty to menopause). Ovarian cysts are less common after menopause.
No known risk factors have been found.
Functional ovarian cysts are not the same as ovarian tumors (including ovarian cancer) or cysts due to hormone-related conditions such as polycystic ovary disease.
Taking fertility drugs can cause a condition called ovarian hyperstimulation, in which multiple large cysts are formed on the ovaries. These usually go away after a woman's period, or after a pregnancy.
Katz VL. Benign gynecologic lesions: Vulva, vagina, cervix, uterus, oviduct, ovary. In: Katz VL, Lentz GM, Lobo RA, Gershenson DM, eds. Comprehensive Gynecology. 5th ed. Philadelphia, Pa: Mosby Elsevier; 2007:chap 18.
A.D.A.M., Inc. is accredited by URAC, also known as the American Accreditation HealthCare Commission (www.urac.org). URAC's accreditation program is an independent audit to verify that A.D.A.M. follows rigorous standards of quality and accountability. A.D.A.M. is among the first to achieve this important distinction for online health information and services. Learn more about A.D.A.M.'s editorial policy, editorial process and privacy policy. A.D.A.M. is also a founding member of Hi-Ethics and subscribes to the principles of the Health on the Net Foundation (www.hon.ch).
© 2011 University of Maryland Medical Center (UMMC). All rights reserved.
UMMC is a member of the University of Maryland Medical System,
22 S. Greene Street, Baltimore, MD 21201. TDD: 1-800-735-2258 or 1.866.408.6885