by Emily Goebel, MD FRCPC
June 6, 2022
Cystic follicles and follicle cysts are related non-cancerous changes commonly seen when the ovary of a reproductive-age woman is examined under the microscope. Both are created by the growth of a normal structure called a follicle that did not release its ovum (egg) during the menstrual cycle. As the follicle grows, an open space called a cyst develops in the center of the follicle.
A cyst that measures less than 3 cm is called a cystic follicle. A cyst that measures more than 3 cm in size is called a follicle cyst. These generally do not cause symptoms. However, a large follicle cyst can rupture and cause pelvic pain.