A cyst could be a fluid-filled sac that forms within the ovary. Ovarian cysts are common and, within the overwhelming majority of cases, they're benign or noncancerous. They vary in size and will occur at different sites within the ovary; the most common type develops when an egg-creating follicle doesn't rupture and release the egg but instead gets big with fluid and forms a follicular cyst.
Cysts usually go away on their own without any procedures or treatments. However, in some cases they'll need surgical removal. In really rare cases, a cyst that distorts or ruptures may trigger serious complex warranting urgent surgery. Any issue regarding these may be addressed better by an Obgyn for Ovarian Cysts.