This tissue lining the inside of the uterus is called the endometrium. Endometriosis is a gynecological disease that occurs when this tissue grows outside of the uterus on the surfaces of pelvic and abdominal organs. Endometriosis can occur on or under the ovaries, behind the uterus, or on the bowels or bladder; in rare occasions, it grows in other parts of the body.1

The tissue that is growing in unusual places still responds to a woman’s menstrual cycle and breaks down on a monthly basis. But, where menstrual blood flows out of the body (from the uterus and through the vagina), tissues associated with endometriosis are trapped inside the body. This causes internal bleeding and inflammation that can lead to pain and more serious complications.2

More than six million girls and women have endometriosis in the U.S. It is most common among women in their 30s and 40s.

Causes of Endometriosis

There are several causes of endometriosis, including:

  • Retrograde Menstruation: Menstrual blood containing endometrial cells flows backward up the fallopian tubes and into the pelvic cavity, where it becomes implanted and grows, and causing endometriosis.
  • Embryonic Cell Growth: Embryonic cells that genetically should become the lining of the abdominal and pelvic cavities instead develop into endometrial cells.
  • Surgical Scar Implantation: During a surgery, like a cesarean section or hysterectomy, endometrial cells may attach to the surgical incision and grow, causing endometriosis.
  • Endometrial Cell Transport: Endometrial cells may travel to other parts of the body through blood vessels or the lymphatic system and become implanted there.
  • Immune System Disorders: As a result of a woman’s impaired immune system, endometrial cells that grow outside of the uterus may not be able to be destroyed, leading to endometriosis.
  • Environmental Factors: There may be a connection between endometriosis and chemicals called dioxins, which come from environmental sources including pesticides, herbicides, industrial waste, and incineration.1

Symptoms of Endometriosis

Symptoms include:1

  • Pain in the abdomen, lower back, and pelvic areas (the pain can occur with menstrual cramps, during or after sex, or be constant)
  • Infertility
  • Painful bowel movements or urination during menstrual periods
  • Heavy menstrual periods
  • Premenstrual spotting
  • Bleeding between periods
  • Intestinal upset during periods (including diarrhea, painful bowel movements, and/or constipation)
  • Yeast infections

Some women don’t have any symptoms of endometriosis; for others, symptoms can or come and go, or get worse over time.

Complications of Endometriosis

  • Formation and possible rupture of cysts that may spread the endometriosis to new areas
  • Intestinal bleeding or obstruction
  • Interference with bladder function

Women who are diagnosed with endometriosis may also be at a higher risk for other health issues, including:

  • Allergies
  • Chemical sensitivities
  • Chronic fatigue
  • Frequent yeast infections
  • Fibromyalgia
  • Hypothyroidism
  • Lupus
  • Multiple Sclerosis
  • Rheumatoid Arthritis
  • Sjögren’s Syndrome

Diagnosis of Endometriosis

Sometimes endometriosis can be felt during a pelvic exam. Your doctor may perform an ultrasound (a procedure that uses sound waves to make an image of internal organs) to look for a specific type of cyst that is common with endometriosis.

Definitive diagnosis requires a laparoscopy because endometriosis can be mistaken for other conditions such as Pelvic Inflammatory Disease (PID), ectopic pregnancy, cysts, appendicitis, diverticulitis, Irritable Bowel Syndrome (IBS), and cancer.

During a laparoscopy, the patient is anesthetized and a thin viewing device (a “laparoscope”) is threaded a small incision; this device is used to check for endometriosis. Often, the surgeon will destroy any visible endometrial lesions that are identified during the diagnosis process.

Treatment of Endometriosis

Home remedies

For mild pain, over-the-counter (OTC) nonsteroidal anti-inflammatory drugs (NSAIDs) pain medications and applying a heating pad to the affected areas can help relieve discomfort.

Exercising regularly and engaging in relaxation techniques, like yoga and meditation, can also relieve symptoms. Some studies have also shown that acupuncture reduces the pain caused by endometriosis.1

Hormone treatments

Hormones are widely used method to treat endometriosis and should be tried before more invasive surgical options. Using oral contraceptives, birth control patches, progestin-only medications (like Depo Provera), or vaginal rings regulates the growth of uterine tissue, and provides relief from endometriosis symptoms. Some women with endometriosis skip the placebo pills in oral contraception packages, in order to prevent their period and further reduce endometriosis-related symptoms.1

Surgical treatment

Operative laparoscopy is the most common surgery to remove endometrial growths and adhesions. The surgeon excises tissue (remove by cutting away with a scalpel) or may use intense heat to destroy areas of endometriosis. About 40-80 percent of women have a recurrence of endometrial pain with two years after surgery.

Hysterectomy is a surgery to remove the uterus and is the last resort for treating endometriosis. If you are considering a hysterectomy to treat endometriosis, remember that there is a chance the endometriosis will recur, even after a hysterectomy. The NWHN believes that less-invasive treatment options should always be explored before hysterectomy is used to address endometriosis.

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  1. Mayo Clinic Website, Endometriosis, Rochester, MN: Mayo Clinic, 2013. Retrieved on June 30, 2015 from:
  2. Endometriosis Association, What is Endometriosis?, Milwaukee: Endometriosis Association, no date. Retrieved on June 30, 2015 from:


Updated August 2015