An ovarian cyst is a collection of excess fluid in the ovary. The formation of fluid around a developing egg is a normal process in all ovulating women, but sometimes, for reasons doctors do not yet understand, too much fluid is formed. The follicle containing the egg expands, forcing the ovary to expand as well, and this may be experienced as pressure or pain in the pelvic area. On the other hand, some women do not feel the cyst at all, and it may only be discovered during a routine gynecological exam.
The vast majority of ovarian cysts are not cancerous, and most of the time they go away by themselves as the fluid is absorbed back into the body. The formation of new cysts can often be prevented by taking birth control pills.
When do cysts need to be removed?
Rarely, a cyst may not go away and surgery may be needed to remove the cyst.
- One scenario is that the cyst causes the ovary to twist around, cutting the blood flow to the ovary and causing severe pain. This is called ovarian torsion.
- Another reason for surgery is the presence of an epithelial ovarian cyst. During ovulation the ovary releases an egg through a tiny rupture in its lining, or epithelium. Normally this closes and heals quickly without incident. Sometimes, however, a few cells from the epithelium make their way into the divot left by the egg and become trapped there during healing. These cells form a fluid that collects and grows into an epithelial ovarian cyst. Because the cyst is trapped inside the ovary, it must be removed surgically.
- A condition called endometriosis can cause a blood-filled ovarian cyst called an endometrioma that will require surgical removal. This type of cyst is formed from endometrial cells (cells from the inner lining of the uterus) that mistakenly traveled up through the fallopian tube into the ovary and began to grow there. Endometrial cells are programmed to grow and bleed with the monthly cycle, and normally they are shed with the menstrual flow. However, if they become trapped inside an ovary, the blood collects and forms a cyst.
- Some ovarian cancers are cystic, so that persistence or increased growth of a cyst as viewed on a sonogram warrants laparoscopic investigation with removal of the cystic tissue for histologic inspection and diagnosis.
- Cysts which are partially solid or have internal wells as determined by ultrasound may also have to be removed.
Since most ovarian cysts in premenopausal women disappear spontaneously, treatment is seldom required. Women who are prone to developing cysts repeatedly may want to use birth control pills to prevent the growth of new cysts until they are ready to bear children.
For cysts that do need to be removed, minimally invasive laparoscopic surgical techniques can now be used to remove these cysts (cystectomy) while preserving the health of the ovary and promising a quick recovery.
- American College of Obstetricians and Gynecologists. Gynecological Problems: Ovarian Cysts. 2005. www.acog.org/publications/patient_education.pdf/bp075.cfm.
- American Society for Reproductive Medicine. Pelvic Pain: A Guide for Patients. Patient Information Series 1997. www.asrm.org/patients/patientbooklets/pelvicpain.pdf.
- Parker WH. A Gynecologist’s Second Opinion. © 2003; A Plume Book; Published by the Penguin Group, New York, NY.
- Parker W. The case for laparoscopic management of the adnexal mass. Clin Obstet Gynecol. 38:362-69.