Most ovarian cysts are normal functional cysts on the ovary. A small proportion of ovarian cysts can enlarge, bleed, cause pain and/or become cancerous.
To understand ovarian cysts, we need to know how the normal ovary functions during a menstrual cycle.
The ovaries are part of the female reproductive system that are regulated by the hormones estrogen and progesterone. Ovulation occurs every month, when the ovary releases an egg under the influence of the hormones. The egg grows inside a tiny fluid-filled sac called a follicle. The follicle breaks open to release the egg as it matures.