An ovarian cyst is a sac filled with fluid that forms on or inside of an ovary.

Ovarian cysts may occur during the process in which an egg is released from the ovary (ovulation). During the days before ovulation, a follicle grows. But when ovulation is supposed to occur, the follicle fails to break open and release an egg, as it is supposed to do. Instead, the fluid stays in the follicle and forms a cyst.

Ovarian cysts are somewhat common, and are more common during a woman's childbearing years (from puberty to menopause). Ovarian cysts are rare 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.

An ovarian cyst can cause pain if it:

• Bleeds
• Breaks open
• Is twisted or causes twisting (torsion) of the fallopian tube
• Pushes on nearby structures

Symptoms of ovarian cysts can include:

• Abnormal uterine bleeding (change from normal menstrual pattern)
  • Absent menstruation
  • Irregular menstruation
  • Longer than usual menstrual cycle
  • Shorter than usual menstrual cycle
• Bloating or swelling in the abdomen
• Pain during bowel movements
• Pain in the pelvis shortly after beginning or ending a menstrual period
• Pain with intercourse or pelvic pain during movement
• Pelvic pain -- constant, dull aching

Note: Often there are no symptoms.

• CT scan
• Doppler flow studies
• MRI
• Pelvic exam
• Ultrasound

The doctor may order the following blood tests:

• Hormone levels (such as LH, FSH, estradiol, and testosterone)
• Serum HCG (pregnancy test)

Functional ovarian cysts usually don't need treatment. Birth control pills (oral contraceptives) may help make cycles normal and decrease the development of functional ovarian cysts.

Simple ovarian cysts that are larger than 5 - 10 centimeters and complex ovarian cysts that don't go away should be removed with surgery (laparoscopy or exploratory laparotomy).

The doctor may recommend other treatments if a disorder, such as polycystic ovary disease, is causing the ovarian cysts.

Functional ovarian cysts usually disappear within 8 - 12 weeks without treatment. Some nonfunctional ovarian cysts must be treated to go away.

Complications have to do with the condition causing the cysts. Complications can occur with cysts that:

• Bleed
• Break open
• Show signs of changes that could be cancer
• Twist

Call for an appointment with your health care provider if you have symptoms of an ovarian cyst.

If you are not trying to get pregnant and you often get functional cysts, you can prevent them by taking hormone medications (such as birth control pills), which prevent follicles from forming.