What is endometriosis?

Endometriosis: Overview

Cells that are like the cells that line the inside of your uterus sometimes grow on the outside of the uterus. This is called endometriosis. These clumps of cells can cause pain and problems with your periods. They can become inflamed and may bleed. Scar tissue that forms over time can make it difficult to get pregnant.

Medicines and sometimes surgery can relieve pain and may help you get pregnant.


Endometriosis (say "en-doh-mee-tree-OH-sus") occurs when cells that are like the cells that line the inside of your uterus grow outside of your uterus. These cells form growths that often attach to the ovaries or other organs, and they may bleed during your period and cause pain. They may also make it hard for you to get pregnant.

Endometriosis can be treated with medicines or with surgery.

What happens when you have endometriosis?

Your uterus is lined with tissue called endometrium. When you have endometriosis, clumps of similar tissue (called implants) form outside your uterus. The implants can be painful. Sometimes they form scar tissue or fluid-filled sacs (cysts). Scar tissue may make it hard to get pregnant.

What are the symptoms of endometriosis?

The most common symptoms are pain, bleeding, and trouble getting pregnant. You may have pain in your lower belly, rectum or vagina, or lower back. And you may have heavy periods, bleeding between periods, bleeding after sex, or blood in your urine or stool. Symptoms often are most severe before and during your menstrual period.

How is endometriosis treated?

Treatment depends on how much pain you have and whether you want to get pregnant. Treatments include:

  • Over-the-counter pain medicines like ibuprofen (such as Advil or Motrin) or naproxen (such as Aleve). These can reduce bleeding and pain.
  • Hormone therapy. This can help reduce pain and menstrual bleeding. It can include hormonal birth control and other medicines.
  • Laparoscopy to remove growths and scar tissue. This may reduce pain, and it may help you get pregnant.

A hysterectomy and oophorectomy (removal of the uterus and ovaries) are sometimes used as a last resort for severe pain.

If you're close to menopause, you may consider treatment with medicines rather than surgery. Endometriosis usually stops causing problems when you stop having periods.

Deciding about hormone therapy (HT) for endometriosis: Overview

Hormone therapy (HT) can often relieve the symptoms of endometriosis. It can be used to reduce pain and bleeding. It may also shrink endometriosis growths (implants) and keep them from spreading.

HT prevents pregnancy, so it's not a good option if you want to get pregnant soon.

What are the types of HT?

Estrogen-progestin therapy plus a nonsteroidal anti-inflammatory drug (NSAID) are often used if symptoms are mild to moderate. If you have severe symptoms, or if estrogen-progestin therapy and NSAIDs don't relieve your symptoms, you may have other HT options. Talk to your doctor about the benefits and risks of the different types of HT.

  • Estrogen-progestin therapy (birth control pills, patch, or ring) may reduce painful periods. It's less likely to cause serious side effects than other hormone treatments. It can often be used continuously for years, until pregnancy is desired or until the age of menopause. It is often used with NSAIDs. These include prescription medicines and over-the-counter NSAIDs, such as ibuprofen (Advil, Motrin) or naproxen (Aleve).
  • Progestin-only therapy stops ovulation and lowers estrogen. It usually shrinks implants and reduces pain. Progestins are given as a shot or a pill. Or you may use the levonorgestrel intrauterine device (IUD).
  • Gonadotropin-releasing hormone (GnRH) therapy lowers estrogen. It triggers a state that's like menopause. This shrinks implants and reduces pain in most cases. GnRH therapy can have more side effects than some other types of HT.
  • Danazol therapy lowers estrogen levels and raises androgen (male sex hormone) levels. It triggers a state that's like menopause. It may shrink implants and reduce pain for several months after treatment. But danazol can have a lot of side effects.

How can you decide if you should take HT?

You might consider taking HT if:

  • Your symptoms are mild to moderate.
  • You don't want to get pregnant soon.
  • You are close to menopause. Your estrogen levels will drop when your menstrual periods end. And you will probably stop having endometriosis symptoms.

You might decide not to take HT if:

  • You want to get pregnant soon.
  • You can manage your pain with other treatments.
  • You want to avoid the possible side effects of HT.

Your doctor can help you weigh the pros and cons of HT so you can decide what's right for you.

Can endometriosis be prevented?

Endometriosis cannot be prevented. This is in part because the cause is poorly understood. But long-term use of birth control hormones (patch, pills, or ring) may prevent endometriosis from becoming worse.

How is endometriosis diagnosed?

Your doctor will ask questions about your symptoms, periods, past health, and family medical history. You may also have a pelvic exam. And you may have imaging tests, such as a pelvic ultrasound or MRI. But to find out for sure if you have endometriosis, a surgery called laparoscopy is often used.

Who can diagnose and treat endometriosis?

Any of the following health professionals can evaluate endometriosis and help you manage the pain:

  • Family medicine physician
  • Gynecologist
  • Internist
  • Nurse practitioner
  • Physician assistant

If your case is complicated or your main problem is infertility, you may be referred to a:

  • Reproductive endocrinologist.
  • Surgeon.

For diagnosis with laparoscopy or for surgical treatment, you may be referred to a gynecologist.

How can you care for yourself when you have endometriosis?

There are things you can try at home to ease the pain of endometriosis. Applying heat to your lower belly may relieve pelvic pain. To relieve back pressure, try placing a pillow under your knees while you lie on your back. Getting regular exercise may also help relieve pain.

How is surgery used to treat endometriosis?

Surgery may be recommended when:

  • Treatment with hormone therapy has not controlled symptoms, and symptoms interfere with daily living.
  • Endometrial growths or scar tissue interferes with other organs in the belly.
  • Endometriosis causes infertility.

Surgery choices include:

  • Laparoscopy. This is the most common procedure for treating endometriosis. It is used to look for and possibly remove growths and scar tissue. It can help relieve pain and can improve the chances of pregnancy for some people. But the pain can come back.
  • Hysterectomy with oophorectomy. This surgery removes the uterus and ovaries. It's used only when you have no plans to get pregnant and have had little relief from other treatments. It can help with pain for the long term. It causes early menopause.

What increases your risk of having endometriosis?

Your risk of endometriosis is higher if:

  • You are between puberty and menopause (around age 50).
  • You have a family history of endometriosis.
  • Your menstrual cycles are less than 28 days.
  • Your menstrual flow is longer than 7 days.
  • You started menstruation before age 12.
  • You have never been pregnant.
  • Your uterus, cervix, or vagina has an abnormal shape that blocks or slows menstrual flow.

What problems can happen when you have endometriosis?

Endometriosis may cause infertility or ovarian problems.

Infertility problems

Experts don't fully understand how endometriosis causes infertility. It could be that:

  • Scar tissue (adhesions) may form at the sites of implants and change the shape or function of the ovaries, fallopian tubes, or uterus.
  • The endometrial implants may change the chemical and hormonal makeup in the fluid that surrounds the organs in the abdominal cavity (peritoneal fluid). This may change the menstrual cycle or prevent a pregnancy.

Ovary problems

A common complication of endometriosis is the development of a cyst on an ovary. This blood-filled growth is called an ovarian endometrioma or an endometrial cyst. The symptoms of an ovarian cyst may be the same as those of endometriosis.

Also, ovarian cancer risk is slightly higher if you have endometriosis.

What causes endometriosis?

Experts aren't sure what causes endometriosis. Problems with reproductive organs may cause endometrial cells to go up through the fallopian tubes and into the belly. And your immune system may not kill these cells outside the uterus like it should. These cells might be carried through the body by blood or lymph fluid.

What is endometriosis?

Endometriosis (say "en-doh-mee-tree-OH-sus") occurs when cells that are like the cells that line the inside of your uterus grow outside of your uterus. These cells form clumps of tissue called implants. They usually grow on the ovaries, the fallopian tubes, the outer wall of the uterus, the intestines, or other organs in the belly. In rare cases, they spread to areas beyond the belly.

Endometriosis usually isn't dangerous. But it can cause pain and other problems.

Endometriosis: When to call

Call your doctor now or seek immediate medical care if:

  • You have severe vaginal bleeding.
  • You have new or worse pain in your belly or pelvis.

Watch closely for changes in your health, and be sure to contact your doctor if:

  • You have unusual vaginal bleeding.
  • You do not get better as expected.

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