When ovulation occurs, the egg, encased in a follicle, is released from the ovary. After ovulation, the empty follicle becomes the corpus luteum. The corpus luteum lingers until the next period. The presence of follicles is normal in the ovary. Follicles are not classified as cysts unless they greater than 2.5-3.0 cm. Cysts may grow as large as 15 cm. Simple cysts are present in 68% of healthy, asymptomatic girls age 2-12.

The most common adnexal mass in teenagers are follicular cysts and corpus luteum cysts. Follicular cysts occur when a dominant follicle fails to rupture or when a nondominant follicle continues to accumulate fluid. Corpus luteum cysts occur when a corpus luteum fills with blood, followed by replacement of the blood with serous fluid.

When follicular cysts rupture, which can occur during sex or spontaneously, they may cause an acute, pelvic pain and rarely bleeding. Some follicular cysts secrete estrogen, which may then delay menses.

Corpus luteum cysts are usually 3-10 cm and moderately tender.

There is no definite way to prevent the growth of ovarian cysts. You should have a physical exam, including a pelvic exam and Pap test, every year or as often as your health care provider recommends. Doing this will help ensure that changes in your ovaries are diagnosed as early as possible.

References

http://www.obgynsi.com/gynecology-ovarian-cysts-pcos-ovarian-cysts-in-teenagers