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Endometriosis - Overview

Definition of Endometriosis:

Endometriosis is a female health disorder that occurs when cells from the lining of the womb (uterus) grow in other areas of the body. This can lead to pain, irregular bleeding, and problems getting pregnant (infertility).

Causes, incidence, and risk factors:

Every month, a woman's ovaries produce hormones that tell the cells lining the uterus (womb) to swell and get thicker. The body removes these extra cells from the womb lining (endometrium) when you get your period.

If these cells (called endometrial cells) implant and grow outside the uterus, endometriosis results. The growths are called endometrial tissue implants. Women with endometriosis typically have tissue implants on the ovaries, bowel, rectum, bladder, and on the lining of the pelvic area. They can occur in other areas of the body, too.

Unlike the endometrial cells found in the uterus, the tissue implants outside the uterus stay in place when you get your period. They sometimes bleed a little bit. They grow again when you get your next period. This ongoing process leads to pain and other symptoms of endometriosis.

The cause of endometriosis is unknown. One theory is that the endometrial cells shed when you get your period travel backwards through the fallopian tubes into the pelvis, where they implant and grow. This is called retrograde menstruation. This backwards menstrual flow occurs in many women, but researchers think the immune system may be different in women with endometriosis.

Endometriosis is common. Sometimes, it may run in the family. Although endometriosis is typically diagnosed between ages 25 - 35, the condition probably begins about the time that regular menstruation begins.

A woman who has a mother or sister with endometriosis is much more likely to develop endometriosis than other women. You are more likely to develop endometriosis if you:

Started your period at a young age
Never had children
Have frequent periods or they last 7 or more days
Closed hymen, which blocks the flow of menstrual blood during the period

Pelvic laparoscopy

Endometriosis

Abnormal menstrual periods

Reviewed last on: 7/25/2011
Susan Storck, MD, FACOG, Chief, Eastside Department of Obstetrics and Gynecology, Group Health Cooperative of Puget Sound, Redmond, Washington; Clinical Teaching Faculty, Department of Obstetrics and Gynecology, University of Washington School of Medicine. Also reviewed by David Zieve, MD, MHA, Medical Director, A.D.A.M., Inc.

References

Lobo R. Endometriosis: etiology, pathology, diagnosis, management. In: Katz VL, Lentz GM, Lobo RA, Gershenson DM. Comprehensive Gynecology. 5th ed. Philadelphia, Pa: Mosby Elsevier; 2007:chap. 19.

Brown J, Pan A, Hart RJ. Gonadotrophin-releasing hormone analogues for pain associated with endometriosis. Cochrane Database Syst Rev. 2010 Dec 8;(12):CD008475.

Giudice LC. Clinical practice. Endometriosis. N Engl J Med. 2010 Jun 24;362(25):2389-98.

de Ziegler D, Borghese B, Chapron C. Endometriosis and infertility: pathophysiology and management. Lancet. 2010 Aug 28;376(9742):730-8.

ACOG Practice Bulletin No. 110: noncontraceptive uses of hormonal contraceptives. Obstet Gynecol. 2010 Jan;115(1):206-18.

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