For Your Patients: What Is Endometriosis?

Endometriosis is a painful disorder that commonly affects the pelvic region but can impact many other body sites as well. An estimated 10% of U.S. girls and women of reproductive age suffer from this under-diagnosed condition.

While endometriosis is generally seen as a disease of adult women, who may not be diagnosed until they are unable to get pregnant and then go for fertility testing, the condition has been found in preadolescent girls. The disease is likely driven by a combination of factors, including genetics, reproductive hormones, and the immune system. Lifestyle and environmental factors may also have an impact.

Once considered to be a disease confined to the female reproductive tract, driven by a woman's menstrual cycle and associated with severe menstrual pain, endometriosis is now seen as a chronic, systemic, disease that triggers inflammation in different parts of the body – not unlike rheumatoid arthritis. It can affect the nerves to increase a woman's overall sensitivity to pain and cause scarring, bleeding, and debilitating inflammation at any time of the month and at multiple different locations, including the heart, brain, diaphragm, spleen, kidneys, and lungs.

The classic hallmark of endometriosis has been abnormally severe pain at menstruation. But this normal monthly process should not involve long-lasting excruciating pain or pain that worsens over time, as in endometriosis, noted Margaret Nachtigall, MD, of NYU Langone Health in New York City. "It is certainly reasonable to seek medical attention, especially because there is often a good solution such as a continuous birth control pill, which might be able to alleviate the pain, as well as other good treatment options."

What Happens in Endometriosis?

Most commonly, the disease has been thought to develop when tissue from the lining of the womb – i.e., the endometrium – escapes from the uterus through the fallopian tubes into the pelvic cavity and continues to grow there.

Implants from this "retrograde menstruation" may then attach to the ovaries, fallopian tubes, or surface of the uterus, as well as the intestines, bladder, rectum, or the space behind the uterus.

Unlike normal menstrual tissue, which leaves the body during a woman's period, this "ectopic tissue" is trapped in the pelvis with no way to exit. Under the influence of hormones regulating the monthly cycle, this ectopic tissue expands and swells, causing bloating, inflammation, scarring, and pain, which is usually more severe and longer lasting than that of typical monthly cramps

Some affected women have no pain and are diagnosed only during investigation for other diseases or when being evaluated for causes of infertility.

More recently, another source of these external deposits has been identified: immature endometrial stem cells produced in bone marrow and at other sites, which travel to distant locations like the brain, heart, diaphragm, or lungs and grow into endometrial-like tissue, causing inflammation, scarring, and pain wherever they take up residence.

The inflammation may be linked to the way a woman's immune system functions, since some sufferers have other immune-related conditions such as asthma, eczema, and other allergies or intolerances. Other factors may be the overproduction of estrogen and fatty hormone-like compounds called prostaglandins, which can cause inflammation and muscle cramping.

How Does Endometriosis Cause Infertility?

The pain of endometriosis can interfere with day-to-day activities as well as fertility, since the displaced tissue can cause inflammation, affecting the eggs, or adhesions, making it harder for the sperm and egg to unite. Scarring may block the ovaries and fallopian tubes, and the inflammation can damage the egg and trigger changes in the uterine lining that make it less receptive to implantation of an embryo.

About 30% to 40% of women with endometriosis become infertile. In more advanced disease, endometriomas -- cysts formed by endometrial tissue growing in the ovaries -- may develop, which can negatively impact the ability to become pregnant.

Early Diagnosis of Endometriosis

It is important to get diagnosed early before the disease progresses. The severity of pain, however, does not always indicate how far the endometriosis extends or what stage of growth it has reached.

Typical Symptoms

• Pain in the lower abdomen around the time of menstruation and usually with severe cramps

• Painful urination or bowel movements or rectal bleeding during menstruation/cyclically

• Pain in the lower abdomen or back at other times, usually cyclic, or unexplained pain at other body sites

• Pain during sexual intercourse

• Periods that last more than 7 days

• Shorter than usual intervals between periods

• Fatigue

• Gastrointestinal problems such as diarrhea, constipation, and nausea during menstruation

• Mood swings and depression

If you have one or more of these symptoms, ask your doctor about getting investigated for endometriosis.

Sometimes surgery may be needed to help with treatment of endometriosis-associated pain.

Risk Factors for Endometriosis

• Having a close relative with endometriosis, which suggests an inherited predisposition

• Starting menstruation before age 12

• Intervals between periods of less than 27 days, leading to more periods per year and thus greater exposure to ovarian hormones

• Anatomical abnormalities in the uterus

• Allergic conditions such as asthma or eczema

• Low body mass index

• Asian race

• Heavy consumption of red meat

Overcoming Reluctance to Seek Help

Gender-based misconceptions may cause some girls and women to brush off their symptoms as normal and avoid seeking help. No woman who suspects she might have endometriosis should allow female stereotyping to condemn her to decades of pain and possible infertility, Nachtigall stressed. "If an individual's physician is not going to evaluate for endometriosis, there are many excellent physicians who do regularly see and take care of patients for endometriosis."

Ask for a referral – or act as your own advocate for getting tested or find someone to advocate for you. The Endometriosis Association can help you find the information and support and connect you with other women who suffer from the condition.

"Medical Journeys" is a set of clinical resources reviewed by doctors, meant for physicians and other healthcare professionals as well as the patients they serve. Each episode of this 12-part journey through a disease state contains both a physician guide and a downloadable/printable patient resource. "Medical Journeys" chart a path each step of the way for physicians and patients and provide continual resources and support, as the caregiver team navigates the course of a disease.