Ovarian Cyst

An ovarian cyst is a fluid-filled sac that develops on an ovary. They're very common and do not usually cause any symptoms.

The 2 main types of ovarian cysts are:

• functional ovarian cysts – cysts that develop as part of the menstrual cycle and are usually harmless and short-lived; these are the most common type
• pathological ovarian cysts – cysts that form as a result of abnormal cell growth; these are much less common

Ovarian cysts can sometimes also be caused by an underlying condition, such as endometriosis.

The vast majority of ovarian cysts are non-cancerous (benign), although a small number are cancerous (malignant).