The American College of Obstetricians and Gynecologists (ACOG) says an ovarian cyst is a sac or pouch filled with fluid or other tissue that forms on the ovary. A woman can develop one or many cysts which can vary in size. They’re usually harmless and disappear on their own. According to the National Institutes of Health (NIH), they’re more common during childbearing years.

The Mayo Clinic says most ovarian cysts start during the menstrual cycle. Ovaries normally grow cyst-like structures called follicles each month. Follicles produce estrogen and progesterone and release an egg during ovulation. Sometimes a normal monthly follicle just keeps growing. When that happens, it becomes known as a functional cyst.

There are two types of functional cysts says WomensHealth.gov. Follicle cysts form when the follicle sac doesn't break open to release the egg and then keeps growing. Corpus luteum cysts form if the sac doesn't dissolve. Instead, it seals off after the egg is released. Then fluid builds up inside.

Most ovarian cysts don’t cause symptoms. When they do, the Mayo Clinic and NIH list symptoms including fullness or heaviness in the abdomen; constant or intermittent dull ache that may radiate to the lower back and thighs; pain during bowel movements or pressure on the bowels; pain in the pelvis shortly before or after a menstrual period; pain with intercourse; nausea, vomiting or breast tenderness; pressure on the rectum or bladder causing a need to urinate more frequently or difficulty emptying the bladder completely. NIH adds menstrual period changes aren’t common with follicular cysts but are with corpus luteum cysts.

WomensHealth.gov says a common treatment for women in their childbearing years, with no symptoms or having a fluid-filled cyst, is watchful waiting. Patients wait for a second exam after one to three months so the doctor can see if the cyst has changed in size.

NIH says surgery may be needed for complex ovarian cysts that don't disappear, for cysts that cause symptoms, for simple ovarian cysts that are larger than five to ten centimeters, and for women who are menopausal or near menopause.

There are two main surgeries according to WomensHealth.gov. Laparoscopy is done if the cyst is small and looks benign. And laparotomy is for larger cysts and/or cancerous ones.

For women who keep forming functional cysts, WomensHealth.gov says doctors may prescribe birth control medication to stop ovulation. If women don’t ovulate, they’re less likely to form new cysts. ACOG added that this treatment won’t make current cysts go away.

The Mayo Clinic advises regular pelvic exams to ensure any ovarian changes are diagnosed as early as possible.

Sources:

Ovarian Cysts. PubMed Health by by National Center for Biotechnology Information and U.S. National Library of Medicine. Web 83 Nov 2011.
http://www.ncbi.nlm.nih.gov/pubmedhealth/PMH0002473

Ovarian Cysts Fact Sheet. WomensHealth.gov by the Office on Women's Health in the Office of the Assistant Secretary for Health at the U.S. Department of Health and Human Services. Web 8 Nov 2011.
http://www.womenshealth.gov/publications/our-publications/fact-sheet/ovarian-cysts.cfm

Ovarian Cysts. ACOG.org by the American College of Obstetricians and Gynecologists. Web 8 Nov 2011.
http://www.acog.org/publications/faq/faq075.pdf

Ovarian Cysts. MayoClinic.com by Mayo Foundation for Medical Education and Research. Web 8 Nov 2011.
http://www.mayoclinic.com/health/ovarian-cysts/DS00129

Reviewed November 14, 2011
by Michele Blacksberg RN
Edited by Jody Smith