Peter T. Simonson, MD, PLLC

Obstetrics and Gynecology


Patient information: Endometriosis

Barbara S Levy, MD, PS
Section Editor
Robert L Barbieri, MD
Deputy Editor
Vanessa A Barss, MD

Last literature review version 18.2: May 2010 | This topic last updated: February 17, 2010 (More)

INTRODUCTION — Endometriosis is a condition where tissue, similar to the tissue that normally grows inside the uterus, also grows outside of the uterus. The tissue inside the uterus is called "endometrium" and the tissue outside of the uterus is called "endometriosis". The most common places where endometriosis occurs are the ovaries, the fallopian tubes, the bowel, and the areas in front, in back, and to the sides of the uterus.

Some women with endometriosis have few of no symptoms while others have pain or difficulty becoming pregnant. There is no cure for endometriosis, but there are several treatment options. The best treatment depends on your individual situation.

More detailed information about endometriosis is available by subscription. (See "Overview of the treatment of endometriosis".)

ENDOMETRIOSIS CAUSES — The cause of endometriosis is not known. A common theory is that some menstrual blood and endometrium flows backwards through the fallopian tubes and into the pelvis during a menstrual period (figure 1). This tissue then grows where it lands in the pelvis. This is called the retrograde menstruation theory. There are several other theories.

ENDOMETRIOSIS SYMPTOMS — Some women with endometriosis have no symptoms. In most women, the most common symptom is pain in the pelvic area.

Pain — Pelvic pain caused by endometriosis can occur:

  • Between menstrual periods, with worsened pain during the period
  • During or after sex
  • With bowel movements or while urinating, especially during the period

Pelvic pain can also be caused by many other conditions, such as pelvic infections and irritable bowel syndrome. A doctor or nurse can help to figure out if endometriosis is the cause of your pain.

Difficulty getting pregnant — Endometriosis can make it more difficult to become pregnant. This might occur because endometriosis causes scar tissue to develop, which can damage the ovaries or fallopian tubes. Even women with endometriosis who do not have scar tissue can have difficulty becoming pregnant.

In women who become pregnant, endometriosis does not harm the pregnancy. Symptoms of endometriosis often improve after pregnancy.

Endometriomas (chocolate cysts) — Women with endometriosis can develop ovarian cysts containing endometriosis; this is called an endometrioma. Endometriomas are usually filled with old blood that resembles chocolate syrup; thus, they are sometimes called chocolate cysts. Endometriomas are sometimes seen during a pelvic ultrasound or felt during a pelvic exam.

ENDOMETRIOSIS DIAGNOSIS — Your doctor or nurse might suspect that you have endometriosis based on your symptoms of pelvic pain or painful menstrual periods. However, the only way to know for sure if you have endometriosis is to have surgery.

Endometriosis is considered mild, moderate, or severe depending on what is found during surgery. Women with mild disease can have severe symptoms, and women with severe symptoms can have mild disease.

In some cases, your doctor will recommend a medicine as the first treatment for endometriosis. This might includes a nonsteroidal antiinflammatory medicine (ibuprofen/Advil®) or hormonal birth control. (See'Endometriosis treatment' below.)

If treatment does not improve your pain or bleeding within 3 to 6 months, surgery is a reasonable next step. (See'Surgery' below.)

In other cases, surgery is performed to diagnose endometriosis and remove it before you take any medicine. Talk to your doctor or nurse about which treatment is right for your situation.

ENDOMETRIOSIS TREATMENT — There are several treatment options for women with endometriosis:

  • Nonsteroidal antiinflammatory drug
  • Hormonal birth control
  • Other forms of hormone treatment (gonadotropin releasing hormone agonists)
  • Surgery

The best treatment depends on your future plans to become pregnant and what symptoms are most bothersome.

Nonsteroidal antiinflammatory drugs — Nonsteroidal antiinflammatory drugs (NSAIDs) are a type of pain medicine that can help to relieve the pain caused by endometriosis. The medicine works by stopping the release of prostaglandins, one of the main chemicals responsible for painful menstrual periods. NSAIDs do not shrink or prevent the growth of endometriosis.

Most NSAIDs are available without a prescription, including:

  • Ibuprofen (sold as Advil, Motrin, and store brands). The recommended dose is 400 to 800 mg every six hours.
  • Naproxen sodium (sold as Aleve and store brands). The recommended dose is 200 to 400 mg at the first dose, then 200 mg every 12 hours.

The disadvantage of NSAIDs is that they do not always relieve endometriosis-related pain. NSAIDs probably work better when combined with another treatment, like hormonal birth control. Serious side effects from NSAIDs, although uncommon, include stomach upset, kidney problems, and worsened high blood pressure.

Hormonal birth control treatments — Hormonal birth control, including the pill, patch, and the vaginal ring are often helpful in treating pain because they reduce heavy bleeding. Hormonal birth control works best in women who do not have severe pain.

Women with endometriosis are often advised to take hormonal birth control continuously for 3 or more months. This allows you to have fewer periods and have less pain and bleeding during each period. This is explained in detail separately. (See "Patient information: Hormonal methods of birth control", section on 'Continuous dosing'.)

The most common side effects of hormonal birth control are:

  • Nausea
  • Breast tenderness
  • Irregular vaginal bleeding or spotting

These side effects usually improve after using the treatment for several months. Serious side effects (eg, blood clots, stroke, heart attack) are rare in women who do not smoke. (See "Patient information: Hormonal methods of birth control".)

Progestins — Progestins are a synthetic form of a natural hormone called progesterone. This treatment might be recommended for women who do not get pain relief from or who cannot take hormonal birth control that contains estrogen (such as smokers). Progestins are available by prescription and usually given as a pill or injection. Progestins are not used if you are trying to become pregnant.

Side effects of progestins can be bothersome for some women. The most common side effects include: bloating, weight gain, irregular vaginal bleeding, and rarely, worsened depression.

Gonadotropin releasing hormone agonists — Gonadotropin releasing hormone (GnRH) agonists are a type of medicine that work by causing a temporary menopause. The treatment causes the ovaries to stop producing estrogen, which causes the endometriosis implants to shrink.

This treatment reduces pain in over 80 percent of women, including women with severe pain. GnRH agonists are not used if you are trying to become pregnant.

Examples of GnRH agonists include:

  • Nafarelin (Synarel®) - Nasal spray taken twice per day
  • Leuprolide (Lupron®) - Shot taken once every one or three months
  • Goserelin (Zoladex®) - Shot taken once every 28 days

Adult women can take the full dose of a GnRH agonist for up to 12 months. There are concerns about using GnRH agonists at full strength for more than 12 months. Women who use GnRH agonists lose bone strength, and this can become serious over time. One way to minimize bone loss is to take hormonal "add-back" treatment in addition to the GnRH agonist.

Taking hormonal add-back can also help to treat the most common side effects of GnRH agonists, which are menopausal symptoms (hot flashes, vaginal dryness, decreased libido, insomnia). (See "Gonadotropin releasing hormone agonists for longterm treatment of endometriosis".)

Surgery — Surgery might be an option to treat endometriosis if you:

  • Have severe pain or bleeding
  • Have tried medicines but still have bothersome pain or bleeding
  • Have a growth or mass in the pelvic area. Surgery is the best way to remove the mass and figure out if endometriosis, or another problem, is the cause.
  • Are having trouble getting pregnant and endometriosis might be the cause.

The goal of surgery is to remove endometriosis implants and scar tissue. More than 80 percent of women who have surgery have less pain for several months after surgery. However, there is a good chance that the pain will come back unless you take some form of treatment after surgery (like hormonal birth control).

Laparoscopy — Laparoscopy is one way to perform surgery, and is commonly used to diagnose and treat endometriosis. During laparoscopy, a doctor makes several small incisions to insert instruments inside the abdomen and pelvis. One of these instruments has a light and camera, which allows the doctor to see the organs on a monitor.

Treatment of an endometrioma — Medicines are unlikely to make an endometrioma go away. Surgery to remove the endometrioma is usually recommended because surgery can confirm the diagnosis, prevent complications (such as rupture of the endometrioma), and treat any symptoms, such as pain. (See "Diagnosis and management of ovarian endometriomas".)

Removal of the uterus or ovaries — Your doctor might recommend surgery to remove your uterus or ovaries or both if:

  • You have tried other treatments but continue to have severe symptoms
  • You do not want to become pregnant in the future
  • You want a permanent treatment
  • Surgery to remove the uterus is called hysterectomy. (See "Patient information: Abdominal hysterectomy".)
  • Surgery to remove the ovaries and fallopian tubes is called salpingo-oophorectomy. It is not always necessary to remove the ovaries to treat endometriosis; this decision will depend on your age and your preferences.

Hormone therapy after surgery — If your ovaries are removed, your doctor or nurse might recommend hormone therapy (estrogen) after surgery. This is especially true for women under age 50 who are not yet menopausal. Estrogen can help to minimize menopausal symptoms like hot flashes, night sweats, vaginal dryness, and weakening of the bones. (See "Patient information: Postmenopausal hormone therapy".)

INFERTILITY TREATMENT — There are several options for treating infertility in women with endometriosis. The best treatment depends on several factors, including your age, if there are other fertility issues, and how severe your endometriosis is. Treatment options include:

More detailed information about endometriosis and infertility is available. (See "Pathogenesis and treatment of infertility in women with endometriosis".)

WHERE TO GET MORE INFORMATION — Your healthcare provider is the best source of information for questions and concerns related to your medical problem.

This article will be updated as needed every four months on our web site (

Related topics for patients, as well as selected articles written for healthcare professionals, are also available. Some of the most relevant are listed below.

Patient level information

Patient information: Painful menstrual periods (dysmenorrhea)
Patient information: Hormonal methods of birth control
Patient information: Abdominal hysterectomy
Patient information: Postmenopausal hormone therapy
Patient information: Infertility treatment with clomiphene (Clomid® or Serophene®)
Patient information: Infertility treatment with gonadotropins
Patient information: In vitro fertilization (IVF)

Professional level information

Diagnosis and management of ovarian endometriomas
Diagnosis and treatment of endometriosis in adolescents
Gonadotropin releasing hormone agonists for longterm treatment of endometriosis
Laparoscopic surgery for treatment of infertility in women
Overview of the treatment of endometriosis
Pathogenesis and treatment of infertility in women with endometriosis
Pathogenesis, clinical features, and diagnosis of endometriosis
Thoracic endometriosis

The following organizations also provide reliable health information.

  • National Library of Medicine


  • The American Congress of Obstetricians and Gynecologists



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2.    ACOG practice bulletin. Medical management of endometriosis. Number 11, December 1999 (replaces Technical Bulletin Number 184, September 1993).Clinical management guidelines for obstetrician-gynecologists. Int J Gynaecol Obstet 2000; 71:183.

3.    Kennedy, S, Bergqvist, A, Chapron, C, et al. ESHRE guideline for the diagnosis and treatment of endometriosis. Hum Reprod 2005; 20:2698.

4.    Allen, C, Hopewell, S, Prentice, A, Gregory, D. Nonsteroidal anti-inflammatory drugs for pain in women with endometriosis. Cochrane Database Syst Rev 2009; :CD004753.

5.    Davis, L, Kennedy, SS, Moore, J, Prentice, A. Modern combined oral contraceptives for pain associated with endometriosis. Cochrane Database Syst Rev 2007; :CD001019.