Illustration overview of Endometriosis

Endometriosis Overview

Endometriosis occurs when the tissue that lines the inside of the uterus begins to grow in places it shouldn't, which can cause debilitating pain and infertility. Around 11% of women have endometriosis, although many remain undiagnosed.

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Endometriosis occurs when the tissue that lines the inside of the uterus begins to grow in places it shouldn't, which can cause debilitating pain and infertility. Around 11% of women between the ages 15 and 44 have endometriosis, although many remain undiagnosed.

What Is It?

Endometriosis is a common condition that most often affects women in their 30s and 40s. It means that the tissue that lines the uterus—the endometrium—is found anywhere outside of the uterus. This tissue is most likely found on reproductive organs and structures, but it can also affect the digestive system as well as these areas:

  • Peritoneum (the membrane lining the cavity of the abdomen and covers the abdominal organs).
  • Ovaries.
  • Fallopian tubes.
  • Uterus and the space behind it, called the cul-de-sac.
  • Bladder.
  • Ureters.
  • Intestines.
  • Rectum.

This tissue can grow and form lesions or scar tissue, cause irregular bleeding, and set off a cascade of inflammation. Endometriosis can cause severe pelvic and gastrointestinal pain and is common in women with infertility. In fact, four in 10 women with infertility are found to have endometriosis.


When it comes to endometriosis lesions, they can be subcategorized into four types:

Superficial endometriosis. Located on the peritoneum (the membrane lining the cavity of the abdomen and covers the abdominal organs)

Cystic ovarian endometriosis. Located on cysts that are on the surface or inside of ovaries. Also called "chocolate cysts."

Deep endometriosis. Located in the recto-vaginal septum (the tissue separating the vagina and rectum), bladder, and bowel. This is a deeply penetrating but rarer form of endometriosis that occurs in one to five percent of women with the condition.

Outside the pelvis. Rarely, endometriosis can be found at a distant location from the pelvis.


Endometriosis is a painful condition, and it can also cause menstrual irregularities and digestive problems. Symptoms include:

Pain. Endometriosis can cause chronic pain that manifests in a variety of ways. Pelvic pain is one of the most frequently reported symptoms, occurring in three-fourths of women with endometriosis. You may also have unusually painful periods, lower back pain, as well as pain during or after sex, which can lead to problems with sexual function and desire.

GI Pain. When it comes to digestive pain, you may also notice pain in the intestines or pain associated with bowel movements or urination when you have your period.

Digestive Problems. This may include diarrhea, constipation, gas and bloating, nausea, painful urination, frequent urination, and, less commonly, blood in urine.

Abnormal Vaginal Bleeding. Whereas your cycle may have been regular before, now you may notice that you bleed or spot in between periods. There are many reasons for spotting and spotting alone does not mean you have endometriosis. In addition, you may also have long, heavy periods. For example, you may bleed through a tampon or pad in one or two hours.

Problems Getting Pregnant. Endometriosis is a leading cause of infertility with up to 30 to 50% of women with the condition struggling to get pregnant. Inflammation and scar tissue can harm egg quality, prevent ovulation, block the fallopian tubes, and impair fertilization and implantation.


Unfortunately, doctors don't know the cause of endometriosis. There are many theories, but it's important to remember that none of them are definitive, and research is ongoing to understand what leads to this outside tissue growth. Experts posit that endometriosis may be caused by genetics, developmental abnormalities in the reproductive system that occurred in utero, backward flow of menstrual blood through the fallopian tubes into the pelvis (commonly known as "retrograde menstruation"), as well as hormonal and immune system issues, among other potential causes.

While having endometriosis is not your fault, there are certain things that put you at a higher risk of developing endometriosis. Risk factors include:

  • Having a mom, sister, or daughter with endometriosis.
  • Starting your period early (before age 11).
  • Having a menstrual cycle that is less than 27 days.
  • A heavy, long period.
  • Being sedentary.


Interestingly enough, the only way to confirm that you have endometriosis is via a surgical procedure called a laparoscopy. The laparoscope will examine your reproductive organs for endometrial tissue and your doctor may also take a biopsy (tissue sample) to test and confirm the diagnosis. The surgical procedure can confirm endometriosis, as well as give doctors an idea of how severe it is. Endometriosis is classified as stage I, II, III, and IV, depending on factors such as the severity, number of lesions and their depth, and the presence of cysts.

Surgery is an invasive procedure, and it won't be the first tool your doctor uses when they suspect endometriosis. Before a laparoscopy, your doctor will also do a pelvic exam, talk to you about your family and health history and your symptoms, and they may order imaging tests like an ultrasound or MRI. Tracking your symptoms can help give your doctor a clearer picture of your day-to-day struggles.


For as life-altering as endometriosis is, the unfortunate news is that there is no cure for the condition. However, endometriosis can be managed to provide symptom relief and improve your quality of life. Your choice may depend on your goals for treatment, including whether or not you would like to get pregnant. Treatment should be individualized, as there's not one right option for everyone.

You doctor may talk to you about these treatments:

Hormonal birth control. A hormonal birth control option, such as an intrauterine device (IUD), extended- or continuous-birth control pills (these reduce or eliminate the number of periods you have in a year) can help reduce the pain associated with your cycle.

Hormone therapy. Gonadotropin-releasing hormone (GnRH) medicines prevent ovulation, stop your periods, and halt the growth of endometriosis. These are designed for short-term use and deliver side effects that mimic menopause, such as hot flashes, fatigue, vaginal dryness, and insomnia.

Surgery. If lesions and scar tissue can be removed, a technique called laparoscopic excision surgery can be done. It may also increase your chances at becoming pregnant. This surgical procedure requires a skilled surgeon who knows how to remove the entire lesion while preserving healthy tissue, so talk to yours about the specific techniques they use and their background with this surgery.

Sometimes, a hysterectomy, surgery that involves removal of the uterus, will be recommended. This is not a cure for endometriosis, as it's common to have lesions outside of the uterus.

NSAIDs. Non-steroidal anti-inflammatory medications, such as ibuprofen and naproxen can quell pain.

Fertility Treatment. Some women with Stage I or II endometriosis may be able to conceive without assistance. However, if you are having trouble getting pregnant, treatment such as fertility medications, intrauterine insemination (IUI), and in-vitro fertilization (IVF) may be options.


Endometriosis cannot be prevented. However, there are some health and lifestyle measures you can take to lower your risk of endometriosis, many of which improve your overall well-being as well. Stick to the Centers of Disease Control and Prevention-recommended limit of one alcoholic drink per day, exercise regularly, don't drink too much caffeine, and consider taking hormonal birth control when you are not looking to get pregnant. All of these may help lower estrogen levels, the hormone that triggers the endometrium to thicken. Becoming pregnant may also help stop the growth of tissue in people who have endometriosis, though it won't prevent it.

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