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 backward 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
Pain is the main symptom of endometriosis. A woman with endometriosis may have:
Pain in the lower abdomen before and during menstruation
Cramps for a week or two before menstruation and during menstruation; cramps may be steady and range from dull to severe)
Pain during or following sexual intercourse
Pain with bowel movements
Pelvic or low back pain that may occur at any time during the menstrual cycle
Note: There may be no symptoms. Some women with a large number of tissue implants in their pelvis have no pain at all, while some women with milder disease have severe pain.
Signs and tests
The health care provider will perform a physical exam, including a pelvic exam. Tests that are done to help diagnose endometriosis include:
If you have mild symptoms and do not ever want children, you may choose to have regular exams every 6 - 12 months so the doctor can make sure the disease isn't getting worse. You can manage your symptoms by using:
Exercise and relaxation techniques
Nonsteroidal anti-inflammatory drugs (NSAIDs), such as ibuprofen (Advil) and naproxen (Aleve), acetaminophen (Tylenol), or prescription painkillers to relieve cramping and pain.
For other women, treatment options include:
Medications to control pain
Hormone medications to stop the endometriosis from getting worse
Surgery to remove the areas of endometriosis or the entire uterus and ovaries
Treatment to stop the endometriosis from getting worse often involves using birth control pills continuously for 6 - 9 months to stop you from having periods and create a pregnancy-like state. This is called pseudopregnancy. This therapy uses estrogen and progesterone birth control pills. It relieves most endometriosis symptoms. However, it does not prevent scarring or reverse physical changes that have already occurred as the result of the endometriosis.
Other hormonal treatments may include:
Progesterone pills or injections. However, side effects can be bothersome and include weight gain and depression.
Gonadotropin-agonist medications such as nafarelin acetate (Synarel) and Depo Lupron to stop the ovaries from producing estrogen and produce a menopause-like state. Side effects include hot flashes, vaginal dryness, and mood changes. Treatment is usually limited to 6 months because it can lead to bone density loss. It may be extended up to 1 year in some cases.
Surgery may be recommended if you have severe pain that does not get better with other treatments. Surgery may include:
Pelvic laparoscopy or laparotomy to diagnose endometriosis and remove all endometrial implants and scar tissue (adhesions).
Hysterectomy to remove the womb (uterus) if you have severe symptoms and do not want to have children in the future. One or both ovaries and fallopian tubes may also be removed. If you do not have both of ovaries removed at the time of hysterectomy, your symptoms may return.
Hormone therapy and laparoscopy cannot cure endometriosis. However, these treatments can help relieve some or all symptoms in many women for years.
Removal of the womb (uterus), fallopian tubes, and both ovaries (a hysterectomy) gives you the best chance for a cure. Rarely, the condition can return.
Endometriosis can lead to problems getting pregnant (infertility). Not all women, especially those with mild endometriosis, will have infertility. Laparoscopy to remove scarring related to the condition may help improve your chances of becoming pregnant. If it does not, fertility treatments should be considered.
Other complications of endometriosis include:
Long-term (chronic) pelvic pain that interferes with social and work activities
Large cysts in the pelvis (called endometriomas) that may break open (rupture)
In a few cases, endometriosis implants may cause blockages of the gastrointestinal or urinary tracts. This is rare.
Very rarely, cancer may develop in the areas of endometriosis after menopause.
Calling your health care provider
Call for an appointment with your health care provider if:
You have symptoms of endometriosis
Back pain or other symptoms come back after endometriosis is treated
Consider getting screened for endometriosis if your mother or sister has been diagnosed with endometriosis, or if you are unable to become pregnant after trying for 1 year.
Birth control pills may help to prevent or slow down the development of the endometriosis.
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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.
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.