What are ovarian cysts?

Ovarian cysts are sacs that form on or inside the ovary. A fluid-filled ovarian cyst is a simple cyst. A complex ovarian cyst contains solid material or blood.

Simple cysts

Simple cysts are common. They develop when your ovary fails to release an egg or when a follicle in your ovary continues to grow after an egg has been released. Because they form due to your normal menstrual cycle, they’re also called functional cysts. Functional cysts usually have no symptoms. They tend to resolve on their own within a few menstrual cycles.

Complex cysts

Complex cysts aren’t related to your normal menstrual cycle, and they’re less common. The following are three common types of complex ovarian cysts:

  • Dermoid cysts are made up of cells you had since before you were born. Your body uses these cells to produce dermal tissue so they may contain fat, skin, hair, or even teeth.
  • Cystadenomas contain ovarian tissue with fluid or mucus.
  • Endometriomas form when cells from your uterine lining grow outside of your uterus and in or on your ovaries.

It’s rare, but ovarian cysts can be malignant. Most ovarian cysts are benign, especially those that develop before menopause.

It’s possible to have small ovarian cysts and not have any symptoms. Some of the more common symptoms of ovarian cysts include:

  • bloating or pressure in your lower abdomen
  • lower abdominal pain
  • nausea and vomiting if the cyst is twisting an ovary
  • frequent urination if the cyst is large enough to press on your bladder
  • sudden, severe pain if the cyst ruptures

Seek immediate medical attention if you have a fever, vomiting, or severe abdominal pain.

If you have endometriomas, the symptoms may include:

It’s often not possible to determine the cause of an ovarian cyst.

Functional cysts occur due to a minor problem, usually involving hormones, in your normal menstrual cycle. Polycystic ovary syndrome (PCOS) is a condition that causes many small, simple ovarian cysts. The exact cause is unknown, but it involves a hormone imbalance.

Read more: What you should know about PCOS and pregnancy »

Endometriomas occur due to a condition called endometriosis, which causes cells from your uterine lining to grow outside of the uterus, including on your ovaries.

Cancerous cysts develop when mutated ovarian cells begin to grow and reproduce.

Ovarian cysts are quite common in women who ovulate. You’re less likely to develop cysts after menopause. If you do develop an ovarian cyst after menopause, it increases your risk for ovarian cancer.

About 8 percent of premenopausal women have a cyst that’s large enough to need treatment.

If you’re experiencing symptoms of a cyst, see your doctor. You’ll probably need a pelvic exam. If your doctor suspects you have a cyst, they may take a wait-and-see approach because most ovarian cysts clear up without treatment. You may also want to take a pregnancy test because pregnancy can cause similar abdominal symptoms.

Other diagnostic tests may include an ultrasound or a CT scan.


An ultrasound uses sound waves to produce real-time images of your ovaries and the surrounding area. It’s fast, safe, and painless. If your doctor suspects an ovarian cyst, they’ll likely use a transvaginal ultrasound to help identify the cyst. For this type of ultrasound, you’ll lie on your back and put your feet in the stirrups. They’ll insert the transducer, which looks like a long rod, a few inches into your vagina to produce images of your ovaries and uterus. The transducer is smaller than the speculum your doctor uses for a Pap test. It only takes a few minutes. It may be slightly uncomfortable, but it doesn’t usually cause pain.

Ultrasound imaging can help determine the location, size, and shape of a cyst. It may also be able to tell if the ovarian cyst is simple or complex.

Ask your doctor if you should arrive with a full or empty bladder. You may need to have one ultrasound done while you have a full bladder and then empty it before having a second one. Alternatively, they may ask you to arrive at the ultrasound appointment with your bladder already empty.

Blood tests

You might also have a blood tests for cancer antigen 125 (CA 125), which is a protein that can be high in women who have ovarian cancer. CA 125 can also be high if you have endometriosis or you’re menstruating. Other blood tests can help determine if you have hormone imbalances.

Learn more: Cysts and ovarian cancer »

Over-the-counter pain relievers may be all you need for a simple cyst. If you have a lot of pain or discomfort, your doctor may be able to prescribe something stronger.

Complex ovarian cysts may need further treatment. Five to 10 percent of women need surgery to remove an ovarian cyst. Thirteen to 21 percent of these cysts turn out to be cancerous.

You may need the cyst removed if it’s growing too large, is painful, or is causing some other problem.

Your doctor can remove some cysts using a small, lighted instrument called a laparoscope.

Your doctor can insert it into your abdomen through a tiny incision. They’ll do this while you’re under anesthesia. Your doctor can remove large or complex cysts that appear to be cancerous with traditional surgery. They can then test the cyst to see if it contains cancerous cells.

If you frequently develop ovarian cysts, your doctor may recommend hormonal birth control. This can help prevent ovulation and lower the chances of developing more cysts.

Treatment for endometriosis can include hormone therapy, pain medications, and surgery.

Most simple ovarian cysts aren’t harmful.

Complex ovarian cysts, such as dermoids and cystadenomas, can grow too large. This can push your ovary out of place. It can also cause a painful condition called ovarian torsion, which means your ovary has become twisted. Cysts can also press against your bladder, causing frequent or urgent urination.

If a cyst ruptures it can cause:

  • severe abdominal pain
  • a fever
  • dizziness
  • weakness
  • rapid breathing
  • vomiting
  • bleeding

If you have any of these symptoms, see your doctor.

Both endometriosis and PCOS can cause fertility problems. Most ovarian cysts aren’t cancerous, but complex ovarian cysts raise the risk of ovarian cancer.

The outlook is generally very good, especially for simple ovarian cysts. What you can expect with a complex ovarian cyst depends on the cause and treatment.

It’s unlikely that you’ll have any long-term health issues once you’ve recovered from surgical removal of a cyst.

Treatment for severe endometriosis can involve surgery and hormonal therapy. In some cases, it leaves scar tissue that can harm your internal organs. About 30 to 40 percent of women with unexplained infertility have endometriosis.

If you have ovarian cancer, your outlook depends on how far the cancer has spread. Treatment options include surgical removal of the ovary, chemotherapy, and radiation. The outlook is best when the doctor diagnoses and treats ovarian cancer in the early stages.