Endometriosis is a common condition that can cause pelvic pain and difficulty getting pregnant.

The “endometrium” is the name for the inner lining of the uterus. In people with endometriosis, cells like those normally found in the endometrium grow outside of the uterus. When these endometriosis cells grow, they cause inflammation, which can lead to symptoms. The most common places where endometriosis occurs are the ovaries, the fallopian tubes, the bowel (large intestine), and the areas in front, in back, and to the sides of the uterus.

There are several medical and surgical treatment options for endometriosis. The best treatment depends on your individual situation.


The cause of endometriosis is not known. A common theory is that some menstrual blood and endometrium flows backward from the uterus through the fallopian tubes and into the pelvis during the monthly menstrual period. This tissue then grows where it lands in the pelvis. This is called the “retrograde menstruation theory.” There are several other theories as well, and research is ongoing to find a cause for this condition.


Some people with endometriosis have no symptoms. The most common symptom is pain in the pelvic area, especially with periods. Endometriosis symptoms typically resolve when a person goes through menopause.

Pain — Pelvic pain caused by endometriosis can occur:

●Just before or during the menstrual period. In some cases, painful periods get worse over time.

●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 be caused by many other conditions, including pelvic floor muscle spasm, pelvic infections, and irritable bowel syndrome. If you have pelvic pain, your health care provider can help to figure out if endometriosis may be the cause.

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

In people who do become pregnant, endometriosis does not harm the pregnancy. In addition, symptoms of endometriosis often improve after pregnancy.

Endometriomas — People with endometriosis can develop ovarian cysts containing endometriosis tissue; these are called endometriomas. 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 examination. They are benign (not cancerous) but can cause pelvic pain; if this happens, surgery is usually recommended to remove them.


Your health care provider might suspect that you have endometriosis if you have pelvic pain or painful menstrual periods. However, the only way to know for sure if you have endometriosis is to have surgery so a doctor can actually see and test (biopsy) the abnormal tissue. If endometriosis is present, they can remove the tissue at this time.

Endometriosis cannot be definitively diagnosed by ultrasound, X-ray, or other noninvasive methods; however, endometriomas are often seen with ultrasound. If you do not feel that your provider is taking your pain seriously, you may want to request an appointment with another provider or clinic. While some amount of discomfort around your period may be normal, endometriosis-related pain should not be dismissed, as there are treatments that can help.

Endometriosis is categorized as mild, moderate, or severe depending on what is found during surgery. However, the category does not always correlate with symptom severity; people with mild disease can have severe symptoms, and people with severe disease can have mild symptoms.

If your symptoms suggest endometriosis, your provider may recommend trying medication to see if it helps, rather than doing surgery right away to confirm the diagnosis.

Your provider can talk with you about which approach to diagnosis and treatment makes the most sense for your situation.


There are several treatment options for endometriosis:

●Nonsteroidal anti-inflammatory drugs (NSAIDs)

●Hormonal birth control

●Other forms of hormone treatment (gonadotropin-releasing hormone analogs)


Each treatment option is discussed in more detail below. The best treatment depends on your symptoms and whether you might want to get pregnant in the future.

Medications — While medications will not get rid of endometriosis, they can help relieve pain. If the medication(s) you try first does not improve your pain within one to three months, your provider may suggest trying another type of medication, or surgery can be discussed as a reasonable next step.

Nonsteroidal anti-inflammatory drugs — NSAIDs are a type of pain medicine that can help to relieve the pain caused by endometriosis. They work by stopping the release of prostaglandins, one of the main chemicals responsible for pain in general as well as painful menstrual periods. Starting these medications one to two days before your period works best to prevent prostaglandin production and therefore reduce menstrual pain. It may take some time, and several doses, for the NSAIDs to block the prostaglandin production and reduce pain. NSAIDs do not shrink or prevent the growth of endometriosis tissue.

Most NSAIDs are available without a prescription, including:

●Ibuprofen (sample brand names: Advil, Motrin) – Follow the package instructions carefully. In general, two tablets are taken for the first dose and one tablet every four to six hours as needed thereafter. These should be taken with food and may be most effective if started one to two days before the onset of pain. Physicians may prescribe higher doses.

●Naproxen (sample brand names: Aleve, Naprosyn) – Follow the package instructions as the dose and frequency differ depending on the formulation. In general, two tablets are taken for the first dose, and one tablet is taken every 8 to 12 hours as needed thereafter, depending on the formulation. All tablets should be taken with food and a full glass of water. Like ibuprofen, naproxen may be more effective if begun a day or two prior to the onset of typical menstrual pain. Physicians may prescribe higher doses.

●Prescription NSAIDs – If over-the-counter NSAIDs are not effective, prescription strengths and formulations may be helpful.

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.

Hormone therapy

Hormonal birth control methods — Hormonal birth control methods, including oral pills, patches, and vaginal rings, are often helpful in treating pain because they reduce or prevent menstrual bleeding, especially when used continuously (only taking active pills or always using the ring in order to skip the monthly period). Daily oral progestin pills as well as injectable and implantable long-acting progestins may be very effective in managing endometriosis-related pain. A progestin-containing intrauterine device (IUD) can also be very effective in treating pain.

The most common side effects of estrogen-containing hormonal birth control are:


●Breast tenderness

●Irregular vaginal bleeding or “spotting” between periods

These side effects usually improve after using the treatment for several months. Serious side effects (eg, blood clots, stroke, heart attack) are rare in people who do not smoke.

Progestins — Progestins are a synthetic form of a natural hormone called progesterone. This treatment might be recommended if you do not get pain relief from or cannot take hormonal birth control that contains estrogen (for example, if you smoke). Progestins require a prescription and are usually given as a pill or injection. They are not used if you are trying to get pregnant. A progestin-containing IUD delivers very low levels of progestin directly to the uterus and results in markedly lighter and less painful periods.

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

Gonadotropin-releasing hormone analogs — Gonadotropin-releasing hormone (GnRH) analogs include GnRH “agonists” and GnRH “antagonists.” Both types of medication cause the ovaries to temporarily stop producing estrogen. This causes the endometriosis tissue to shrink.

This treatment reduces pain in over 80 percent of people, including those with severe pain. GnRH analogs are not used if you are trying to get pregnant.

Examples of GnRH agonists include:

●Nafarelin (brand name: Synarel) – Nasal spray taken twice per day

●Leuprolide (brand name: Lupron) – Shot taken once every one or three months

●Goserelin (brand name: Zoladex) – Shot taken once every 28 days

An example of a GnRH antagonist includes:

●Elagolix (brand name: Orilissa) – Oral tablet taken twice daily

Adults can take the full dose of a GnRH agonist for up to 12 months or a GnRH antagonist for up to 24 months. For GnRH analogs, there are concerns about weakening of the bones (bone loss) over time. One way to minimize bone loss is to take hormonal “add-back” treatment (adding very small amounts of either estrogen or a synthetic progestin) in addition to the GnRH analog.

Taking hormonal add-back can also help to treat the most common side effects of GnRH analogs (hot flashes, vaginal dryness, decreased libido, insomnia).

Aromatase inhibitors — These drugs block a specific enzyme (aromatase) that increases estrogen levels in tissue. There is increasing evidence that endometriosis tissue makes its own aromatase.

Examples of aromatase inhibitors include letrozole and anastrozole. Both medications are pills that are taken once a day. Combining these drugs with hormonal birth control, progestins, or GnRH agonists may be more effective than any of them alone. This may be a strategy for long-term management of endometriosis pain in people who do not want to get pregnant since the side effects appear to be minimal.

Surgery — As discussed above, in some cases, surgery is done to diagnose endometriosis (and possibly remove it) before you try treatment with medication. Other times, surgery is considered when medications do not work well enough to relieve pain.

Surgery can often be done “laparoscopically.” For this approach, a doctor makes several small cuts to place 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 screen. Laparoscopy is less invasive than open surgery (in which a larger incision is made in the abdomen) and is often associated with a shorter recovery time.

Doctors use different methods to remove or destroy endometriosis tissue during surgery. Surgery might be an option to treat endometriosis if you:

●Have severe pain that is localized to a specific area and tender on examination.

●Have tried medicines but still have bothersome endometriosis-related pain in a specific spot on pelvic examination.

●Have a growth or mass in the pelvic area. Surgery may be necessary to remove the mass and figure out if endometriosis, or another problem, is the cause.

●Are having trouble getting pregnant (and your provider thinks endometriosis might be the cause).

The goal of surgery is to remove endometriosis and scar tissue. Approximately 75 percent of people who have this surgery have less pain for several months after surgery. However, surgery is not a permanent cure, and there is a good chance that the endometriosis tissue will eventually grow back and your pain will return unless you take some form of treatment after surgery, such as hormonal birth control.

In some cases, rather than just removing or destroying endometriosis tissue, the entire uterus (and sometimes the ovaries) is removed. This is typically reserved for people who continue to have severe symptoms despite other treatments and who do not wish to become pregnant in the future.

Endometrioma treatment — Medications are unlikely to make an endometrioma (“chocolate cyst”) go away. Surgery is usually recommended to remove an endometrioma if it is larger than 4 to 5 cm, symptomatic, or enlarging; this is because surgery can confirm the diagnosis, prevent complications (such as rupture of the endometrioma), and relieve symptoms (such as pain). Removing smaller endometriomas is not recommended because their relationship to infertility is unclear, and surgery on the ovary will diminish its ability to produce eggs over time. However, small endometriomas may enlarge over time and start to cause symptoms, at which point they can be removed.

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. More information about this procedure is available separately.

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 preferences. If your ovaries and fallopian tubes are removed, your body will no longer produce estrogen and you will stop having your monthly period; this is called “surgical menopause.” In some situations, hormone treatment is recommended after surgery.


There are several options for treating infertility related to endometriosis. The best treatment depends on individual factors, including your age, whether you have other fertility issues, and how severe your endometriosis is. Treatment options include:

●Medication to cause ovulation, such as clomiphene, anastrozole, or letrozole.

●Fertility medicines plus intrauterine insemination (IUI).

●Surgery to remove endometriosis tissue.