Cyst on the Ovary

An ovarian cyst is a closed sac or pouch that forms on or in an ovary. The ovaries are glands in the female reproductive system, which produce hormones and sex cells (eggs or ova). Ovarian cysts can be solid masses, may be filled with fluid, or can contain a mixture of fluid and solid material. Many ovarian cysts do not pose serious problems, but they may be painful and can be cancerous (malignant).

Ovarian cysts may form during a normal menstrual cycle. These cysts, which are called functional cysts, develop when there is a problem with the sac that holds the egg before it is released (follicle) into the fallopian tube.

There are two kinds of functional cysts. Follicular cysts develop when the follicle does not release an egg. This type of ovarian cyst usually does not cause pain or require treatment. In most cases, follicular cysts go away on their own within 3 months.

Corpus luteum cysts are functional cysts that occur after an egg is released. Normally, after the egg is released, the follicle produces hormones needed for conception (called a corpus luteum). In some cases, the hole from which the egg is released closes and fluid accumulates, forming a corpus luteum cyst. This type of ovarian cyst may resolve without treatment, but can bleed, rupture (break), and cause ovarian torsion (i.e., twisting of the ovary).

Other types of ovarian cysts include dermoid cysts, which form from an egg cell and may contain teeth, skin, or hair tissue; endometriomas, which form from uterine cells; and cystcidenomas, which can grow to a diameter of 12 inches or larger.

Ovarian cysts usually do not cause symptoms. When symptoms do occur, they often include changes in the menstrual cycle, abnormal vaginal bleeding, bowel pain, pelvic pain, urinary problems, and nausea.

Most ovarian cysts are discovered during a routine pelvic exam. Diagnostic tests, including pregnancy tests, ultrasound, blood tests (e.g., CA 125), and tests to measure hormone levels, can be used to learn more about the size and shape of the cyst and determine whether it is solid, fluid-filled, or a combination. In some cases, magnetic resonance imaging (MRI scan), computed tomography (CT scan), or Doppler flow studies also are performed.

Ovarian cyst treatment depends on the type and size of the cyst and on the severity of the symptoms. If the cyst is filled with fluid and is not causing any symptoms, doctors might recommend frequent checkups to make sure the cyst does not get larger (called watchful waiting).

An ovarian cyst that grows bigger or causes pain usually requires surgery. Laparoscopy is a common procedure used to treat ovarian cysts. In this procedure, the doctor makes a small incision in the abdomen and uses a thin instrument called a laparoscope to locate and remove the cyst


If the cyst is large or ovarian cancer is suspected, a laparotomy usually is performed. During this surgery, the cyst can be tested for cancer cells before it is removed. If the cyst is cancerous, the affected ovary, other tissues, and/or the uterus also may be removed.

Ovarian cysts cannot be prevented, so women are advised to get regular pelvic exams.

Publication Review By: Stanley J. Swierzewski, III, M.D.

Published: 29 Oct 2009

Last Modified: 29 Sep 2015