An ovarian cyst is a sac filled with fluid, or a semisolid material, that develops on or within the ovary. Ovarian cysts are relatively common and usually disappear without treatment.
Review Date 1/10/2022
Updated by: John D. Jacobson, MD, Department of Obstetrics and Gynecology, Loma Linda University School of Medicine, Loma Linda, CA. Also reviewed by David Zieve, MD, MHA, Medical Director, Brenda Conaway, Editorial Director, and the A.D.A.M. Editorial team.