Health library

Back to health library

Understanding ovarian cysts

 Illustration of four women with red lipstick.

Most ovarian cysts are harmless, but some should be treated right away.

Most ovarian cysts are nothing to worry about. But others can cause severe symptoms or permanent damage. Some can develop into ovarian cancer.

Overall, ovarian cysts shouldn't send anyone into a panic. But they should get you to a doctor.

Types of ovarian cysts include:

Functional cysts

The two types of functional cysts are follicle and corpus luteum cysts. Together, these are the most common ovarian cysts. They're formed during ovulation, or egg production. During a normal menstrual cycle, an egg matures, grows and leaves the ovary. While it grows, the egg is enclosed in a fluid-filled sac called a follicle. Once the egg has matured, the sac breaks open so the egg can leave the ovary. The sac then dissolves into corpus luteum, a mass that produces hormones for the next egg.

  • Follicle cysts occur when the sac doesn't break open and release the egg. Then the sac keeps growing. Most follicular cysts will dissolve on their own within three menstrual cycles.
  • Corpus luteum cysts form if the sac doesn't dissolve after releasing the egg. If this happens, the follicle seals off and grows larger as fluid builds up inside. Most of these cysts go away after a few weeks.


These cysts are the result of endometriosis, a condition in which uterine tissue grows outside the uterus. When this tissue grows on an ovary, it can form a cyst called an endometrioma. These cysts can cause pain during your period and during sex.

Dermoid cysts

Dermoid cysts form from cells that usually make eggs. They can contain tissue such as skin, hair and bone. These cysts can grow quite large and cause pain but are rarely cancerous.

Polycystic ovary syndrome

This condition can prevent eggs from being released by the ovary. The follicles remain in the ovary and turn into cysts. As this process repeats, the ovary may eventually be covered with many cysts that continue to grow.


Most ovarian cysts are small and don't cause symptoms, according to the American College of Obstetricians and Gynecologists (ACOG). Large cysts, ruptured cysts or endometriomas may produce:

  • Abdominal swelling.
  • Pain during sexual intercourse.
  • Severe abdominal pain.
  • Nausea.
  • Fever.
  • Unusually painful menstrual periods.
  • Abnormal vaginal bleeding.

Finding a cyst

According to ACOG, most cysts are found during a routine pelvic examination. To find out what kind of cyst it is, ultrasound is typically used.

Ultrasound creates an image of the ovaries by passing sound waves through your abdomen.  


Some cysts require immediate treatment, and others don't need to be treated at all. This decision depends on the size and type of the cyst, your health and symptoms, your future plans for pregnancy, and your age.

Possible treatments include watchful waiting; medications, including birth control pills; and surgery.

Reviewed 6/23/2022

Related stories