An ovarian cyst is a fluid-filled sac that develops on an ovary. They're very common and do not usually cause any symptoms.
Ovarian cysts are fluid-filled sacs that can grow on the ovaries. Most cysts are harmless and disappear without treatment.
Some ovarian cysts can cause symptoms, such as pain in your tummy, bloating and irregular periods.
Most ovarian cysts disappear in a few months without treatment. Large cysts or cysts causing symptoms may need to be surgically removed.
Most ovarian cysts are a normal part of the menstrual cycle. Some can be caused by abnormal cell growth or a condition such as endometriosis.
Page last reviewed: 23/12/2016
Next review due: 23/12/2019