An ovarian cyst is a collection of fluid that comes from an ovary. An ovarian cyst is a collection of fluid that comes from an ovary.
Many cysts are completely normal.
These are called functional cysts. In women who are having periods, functional cysts are normal. Functional cysts will normally shrink over time, usually in about one to three months. If you have a functional cyst, your doctor may decide to do nothing except see you again in one to three months to make sure the cyst has gotten smaller. Or your doctor may want you to take birth control pills, so you won't ovulate.