Ovarian Cysts

Sometimes girls are told that they have a cyst “on” their ovaries but cysts develop within the ovary. Fortunately most cysts go away without any treatment.

What are ovaries and ovulation?

You have two, small, grape-shaped organs called ovaries inside of your abdomen (belly) on each side of your uterus. When you are born, your ovaries are already filled with millions of eggs. When you reach puberty, chemicals from the pituitary gland in your brain signal your ovaries to ripen an egg. Usually, once a month an egg is released from a fluid-filled sac in the ovary so it can travel through the fallopian tube to the uterus. This is called ovulation, which is part of your monthly cycle. The “fluid-filled” sac is sometimes 3 cm (about 1 inch) across and on an ultrasound report called a “cyst” but it is normal.

What are ovarian cysts?

A cyst is a fluid-filled sac that develops in the ovary and usually disappears after ovulation. There are different types of cysts.

Follicular cyst – A follicular cyst develops each month and contains a tiny egg within it. The sac ruptures during ovulation and the egg leaves the ovary. Sometimes the cyst can grow larger than the normal size which is up to 3 cm (a little over an inch). If the sac that holds the egg doesn’t break open to release the egg, it can grow, anywhere in size from ½ inch (1 cm) to 4 inches (10 cm) across. Most follicular cysts will disappear in 2-8 weeks and do not cause pain. Large cysts may or may not cause pain and/or pressure in the lower belly (on the side where the cyst is) and usually takes longer to resolve or go away. Your health care provider (HCP) may find that you have a follicular cyst during a pelvic exam or by a test called an ultrasound.

Corpus luteum cyst – A corpus luteum cyst is normal and usually forms each month after ovulation. This type of cyst usually disappears by itself in a few weeks, but it can sometimes take up to three months. A corpus luteum cyst can grow 3-4 inches across, and may bleed inside of the cyst or your belly and cause pain.

Polycystic Ovary Syndrome (PCOS) – pronounced “poly-sis-stick” “o-va-ree” syndrome actually means many cysts in the ovary. Some girls with this condition have lots of tiny cysts  inside of their ovaries, and others do not. This type of ovarian cyst is not harmful, does not have to be removed, and almost never causes pain.

I have pain on my side every month or so, is this normal?

Some girls and women have pain on one side or the other below their belly button about 2 weeks before they get their periods. Others do not. This is called “Mittelschmerz” – pain or discomfort which occurs during ovulation. This kind of pain is usually mild and lasts anywhere from 1 hour to 1-2 days. However, if you have severe pain it could be caused by other problems, so you should check with your health care provider or go to a nearby emergency room.

How are ovarian cysts diagnosed?

Because most ovarian cysts do not cause symptoms and go away on their own, they may be completely unnoticed. If you have pain or irregular periods that prompt you to see your health care provider (HCP), you may need to have a pelvic ultrasound to see if you might have a cyst. If you have a cyst, your HCP will be able to see it on the ultrasound.

What is a pelvic ultrasound?

A pelvic ultrasound is a test that uses sound waves to make a picture of your reproductive organs (i.e. ovaries and uterus) and bladder (where your urine is stored). It is usually necessary to have a full bladder before the procedure. This means you will need to drink a lot of water before you arrive for the test. The test itself is not painful, but you may feel a little uncomfortable since your bladder will be full until you pass urine (pee) after the test.

You will lie on your back on an exam table while the sonographer (the person who performs the ultrasound) places a warm gel on your lower belly with something that looks like a microphone. The sonographer will gently move this microphone-like instrument around your abdomen (belly).  This is called a “transabdominal” ultrasound. You will probably feel a little bit of pressure but you shouldn’t feel any pain. The instrument actually makes a picture by picking up sound waves. From these pictures your health care provider will know if you have an ovarian cyst or not. If you have a cyst, your health care provider will most likely repeat the pelvic ultrasound in about 2-8 weeks to make sure that the cyst is getting smaller or is gone completely.

The ultrasound is usually performed on your belly, but sometimes an ultrasound is performed with a probe that is inserted into the vagina and is called a “transvaginal” ultrasound.  Transvaginal ultrasounds are helpful if the sonographer has trouble capturing a clear picture of your ovaries through a transabdominal ultrasound. Typically the transvaginal ultrasound isn’t painful, but it can be  uncomfortable if you have not used tampons or had vaginal sex.  Talk with the sonographer before they start a transvaginal ultrasound to make sure they know your concerns and have had experience with transvaginal exams in teens.

What happens if I have an ovarian cyst?

Because most ovarian cysts usually go away on their own, you don’t need to worry if you have one. Your health care provider (HCP) will want you to let them know if you have abdominal or belly pain. Mild pain in your belly can last for several weeks, but if you have moderate to severe pain that makes it very hard for you to walk, you vomit, or you feel like passing out, see your HCP right away or go to the closest emergency room. Your HCP might also tell you not to exercise or participate in sports until the cyst becomes small or goes away completely. This is because moderate to extreme activity might cause your ovary to twist on itself which is a condition that requires emergency care.

Can ovarian cysts be dangerous?

An ovarian cyst usually doesn’t cause any problems, but occasionally it may cause the ovary to twist on its root. This is called “torsion”. Torsion blocks the blood from going to the ovary. If this were to happen, you would have severe abdominal pain and you might feel like throwing up or even feel like passing out. If you have any of these symptoms, you should see your HCP immediately or go to the closest hospital emergency room.

Rarely an ovarian cyst may not go away on its own and needs to be removed. In this case, a surgeon would remove the cyst while leaving the rest of the ovary in place. Very rarely this type of persistent cyst might be related to another problem, such as a benign tumor or very, very rarely cancer.

Can ovarian cysts be prevented?

If you have a large ovarian cyst or a history of developing ovarian cysts, your HCP may prescribe birth control pills to prevent your body from ovulating. This lowers your chances of forming new cysts in the future but doesn’t make the cyst you already have go away any faster. Talk to your HCP to find out if birth control pills are right for you.

Our health guides are developed through a systematic, rigorous process to ensure accuracy, reliability, and trustworthiness. Written and reviewed by experienced healthcare clinicians from Boston Children's Hospital, a Harvard Medical School teaching hospital and consistently ranked as a top hospital by Newsweek and U.S. News & World Report, these guides combine clinical expertise, specialized knowledge, and evidence-based medicine. We also incorporate research and best practices from authoritative sources such as the CDC, NIH, PubMed, top medical journals, and UpToDate.com. Clinical specialists and subject matter experts review and edit each guide, reinforcing our commitment to high-quality, factual, scientifically accurate health information for young people.