An ovarian cyst is a sac filled with fluid that forms on or inside an ovary.
This article is about cysts that form during your monthly menstrual cycle, called functional cysts. Functional cysts are not the same as cysts caused by cancer or other diseases.
Each month during your menstrual cycle, a follicle grows on your ovary. The follicle is where an egg is developing. Most months, an egg is released from this follicle, called ovulation. If the follicle fails to break open and release an egg, the fluid stays in the follicle and forms a cyst. This is called a follicular cyst.
Another type of cyst occurs after an egg has been released from a follicle. This is called a corpus luteum cyst. This type of cyst often contains a small amount of blood.
Ovarian cysts are more common in the childbearing years between puberty and menopause. The condition is less common after menopause.
Taking fertility drugs can cause a condition in which multiple large cysts are formed on the ovaries. This is called ovarian hyperstimulation syndrome. The cysts most often go away after a woman's period, or after a pregnancy.
Functional ovarian cysts are not the same as ovarian tumors, or cysts due to hormone-related conditions such as polycystic ovary syndrome.
Ovarian cysts often cause no symptoms.
An ovarian cyst is more likely to cause pain if it:
- Becomes large
- Breaks open
- Interferes with the blood supply to the ovary
- Is bumped during sexual intercourse
- Is twisted or causes twisting (torsion) of the fallopian tube
Symptoms of ovarian cysts can also include:
- Bloating or swelling in the abdomen
- Pain during bowel movements
- Pain in the pelvis shortly before or after beginning a menstrual period
- Pain with intercourse or pelvic pain during movement
- Pelvic pain -- constant, dull aching
- Sudden and severe pelvic pain, often with nausea and vomiting, may be a sign of torsion or twisting of the ovary on its blood supply, or rupture of a cyst with internal bleeding
Changes in menstrual periods are not common with follicular cysts, and are more common with corpus luteum cysts. Spotting or bleeding may occur with some cysts.
Exams and Tests
Your health care provider may discover a cyst during a pelvic exam, or when you have an ultrasound test for another reason.
Ultrasound may be done to diagnose a cyst. Your provider may want to check you again in 6 to 8 weeks to make sure it is gone.
Other imaging tests that may be done when needed include:
The following blood tests may be done:
Functional ovarian cysts often do not need treatment. They often go away on their own within 8 to 12 weeks.
If you have frequent cysts, your provider may prescribe birth control pills (oral contraceptives). These medicines may reduce the risk of developing new ovarian cysts. Birth control pills do not decrease the size of current cysts.
Surgery to remove the cyst or ovary may be needed to make sure that it is not ovarian cancer. Surgery is more likely to be needed for:
- Complex ovarian cysts that do not go away
- Cysts that are causing symptoms and do not go away
- Simple ovarian cysts that are larger than 10 centimeters
- Women who are near menopause or past menopause
Types of surgery for ovarian cysts include:
You may need other treatments if you have polycystic ovary syndrome or another disorder that can cause cysts.
Cysts in women who are still having periods are more likely to go away. A complex cyst in a woman who is past menopause has a higher risk of being cancer. Cancer is very unlikely with a simple cyst.
Complications have to do with the condition causing the cysts. Complications can occur with cysts that:
- Break open.
- Show signs of changes that could be cancer.
- Twist, depending on size of the cyst. Bigger cysts carry a higher risk.
When to Contact a Medical Professional
Call your provider if:
- You have symptoms of an ovarian cyst
- You have severe pain
- You have bleeding that is not normal for you
Also call your provider if you have had following on most days for at least 2 weeks:
- Getting full quickly when eating
- Losing your appetite
- Losing weight without trying
If you are not trying to get pregnant and you often get functional cysts, you can prevent them by taking hormone drugs (such as birth control pills). These medicines prevent follicles from growing.
Physiologic ovarian cysts; Functional ovarian cysts; Corpus luteum cysts; Follicular cysts
Bulun SE. The physiology and pathology of the female reproductive axis. In: Melmed S, Polonsky KS, Larsen PR, Kronenberg HM, eds. Williams Textbook of Endocrinology. 13th ed. Philadelphia, PA: Elsevier; 2016:chap 17.
Katz VL. Benign gynecologic lesions. In: Lentz GM, Lobo RA, Gershenson DM, Katz VL, eds. Comprehensive Gynecology. 6th ed. Philadelphia, PA: Elsevier Mosby; 2012:chap 18.
Review Date 4/5/2016
Updated by: Irina Burd, MD, PhD, Associate Professor of Gynecology and Obstetrics at Johns Hopkins University School of Medicine, Baltimore, MD. Review provided by VeriMed Healthcare Network. Also reviewed by David Zieve, MD, MHA, Isla Ogilvie, PhD, and the A.D.A.M. Editorial team.