An ovarian cyst is a fluid-filled pocket in or on the ovary. These cysts are common. There are different types of cysts based on where they develop or what material is in the cyst.

Close Up of Ovary and Fallopian Tube
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There are a variety of reasons an ovarian cyst may develop depending on the type.

Functional cysts are the most common type of ovarian cyst. It is normal for cysts to develop as part of the ovulation cycle. However, functional cysts remain or grow. Types of functional cysts include:

  • Follicular cyst—Ovaries have a number of follicles (a fluid-filled sac) that each contain an egg. During the ovulation process, a follicle should release the egg. A follicular cyst is caused by an egg that is not released. The follicle, trapped egg, and fluids make up the cyst.
  • Corpus luteum cyst—The egg is released, but the follicle closes up causing excess fluid to collect and create a cyst

Other, less common types of ovarian cysts include:

  • Teratoma or dermoid cyst—May be present from birth or develop later in life. Can include tissue from other parts of the body like teeth and hair.
  • Endometrioma—Caused by endometriosis, a condition that allows uterine tissue to grow outside of the uterus. Cysts may grow and become filled with fluid, often blood.
  • Cystadenoma—Grows from cells that line the outside of the ovary. Can become large and painful.

Some cysts can also be caused by pelvic infections that have spread to the ovaries.

Risk Factors

Cysts are more common in women with regular, monthly menstrual cycles. However, women can still develop cysts after menopause. Other factors that may increase the risk of cysts include:

  • Previous ovarian cysts
  • Hormonal changes—may happen during ovulation cycle or in response to certain fertility medication
  • Endometriosis
  • Pregnancy—a cyst is a normal part of early pregnancy but cysts that remains through pregnancy may cause problems
  • Severe pelvic infection


Most ovarian cysts do not cause symptoms and will go away on their own. Others may need care. Cysts that are large or leak fluid may cause:

  • Bloating
  • Pain and pressure in lower abdomen—may be felt on side that the cyst has developed
  • Problems with urination or feeling the urge to urinate a lot (if it is pressing on bladder)
  • Pain during sex
  • Ache in legs or lower back
  • Abnormal bleeding

The fallopian tube may become twisted because of the cyst or a cyst may rupture. This can cause severe pain, nausea, vomiting, or bleeding that will require medical care.


You will be asked about your symptoms and medical history. A pelvic exam will also be done. Cysts are often found during routine pelvic exams. The doctor can determine factors like size that will help decide if more testing is needed.

Further testing may not be needed or may be delayed to see if the cyst goes away on its own. If the cyst is large, is not going away, or is causing severe problems, then tests may include:

  • Ultrasound —to see size and location of cyst and whether it is fluid or solid filled
  • Pregnancy test—a positive test may indicate a certain type of cyst, can also exclude ectopic pregnancy (pregnancy that develops outside of the uterus)
  • Blood test—to look for a protein called CA 125 which may increase with certain conditions like endometriosis and ovarian cancer


Many cysts will go away without treatment. For example:

  • Follicular cyst—often goes away within 1-3 menstrual cycles
  • Corpus luteum cyst—often goes away within in a few weeks

If a cyst is found, it may simply be monitored for any changes.

For cysts that are causing problems, treatment will depend on factors like age, menstrual status, type of cyst, and symptoms.

  • Cysts that develop in women over 40 years of age have a higher risk of developing into cancer. These cysts will be closely monitored for changes, or may be removed as precaution.
  • Cysts that are large, growing, solid, or remain longer than 2-3 menstrual cycles may be removed.
  • Cysts that are causing severe bleeding or pain may require emergency surgical removal.
  • The fallopian tube may become twisted because of the cyst
  • The cyst may rupture

Most operations for ovarian cysts can be done with laparoscopy. This surgery uses small incisions to reach the cysts to help decrease recovery time.

When possible the cyst will be removed and the ovary will be left in place. Sometimes the ovary will need to be removed. Ovaries provide hormones that stimulate menstruation. If both ovaries are removed, menopause will begin right away.


If you have frequent problems, talk to you doctor about ways to reduce your risks.


American Congress of Obstetricians and Gynecologists

Office on Women's Health—US Department of Health and Human Services


Canadian Cancer Society

The Society of Obstetricians and Gynaecologists of Canada


Adnexal mass. EBSCO DynaMed Plus website. Available at: Updated May 10, 2017. Accessed December 12, 2017.

Ovarian cysts. Office on Women's Health—US Department of Health and Human Services website. Available at: Updated April 28, 2017. Accessed December 12, 2017.

Benign ovarian masses. Merck Manual Professional Version website. Available at: Updated March 2017. Accessed December 12, 2017.

Last reviewed November 2018 by Beverly Siegal, MD, FACOG  Last Updated: 4/3/2018