What is Endometriosis?

Posted on August 21, 2018

Article written by
Kelly Crumrin

Endometriosis is a painful, chronic disease that affects approximately one in 10 women. Endometriosis often goes unrecognized by doctors or is misdiagnosed and incorrectly treated. Endometriosis can have a profound impact on quality of life, including work, education, relationships, and the ability to conceive. Endometriosis can be particularly disruptive during a woman’s period. A woman with endometriosis may suffer for many years before obtaining the correct diagnosis, as symptoms can be confused with pelvic inflammatory disease (PID), irritable bowel syndrome (IBS), fibromyalgia, and other illnesses. Diagnosis may be further complicated by the presence of multiple chronic conditions.

What causes endometriosis?

The endometrium is the lining of the uterus that builds up each month, breaks down, and sheds during the menstrual period. Endometriosis occurs when tissue similar to endometrial tissue exists outside of the uterus.

Endometrial tissue growing outside the uterus develops into growths (also called implants or lesions) which respond to the menstrual cycle. Like the lining of the uterus, endometrial growths respond to the hormonal changes that bring about menstruation. But unlike the endometrium in the uterus, endometrial growths have no way of leaving the body. This results in internal bleeding, breakdown of the blood and tissue from the growths, and inflammation that causes pain, scarring, adhesions, infertility, and other problems. Read more about the causes of endometriosis.

Where can endometriosis occur?

Endometriosis can occur anywhere in the pelvic cavity. Endometriosis most commonly involves a woman’s ovaries, fallopian tubes, the ligaments that support the uterus, the spaces around the reproductive organs, and the tissue lining the pelvic cavity. Endometrial tissue may also spread to organs such as to the bladder or bowel.

The history of endometriosis

Throughout history, the symptoms of severe, chronic pelvic pain in women were often attributed to mental illness, demonic possession, or promiscuity. Hysteria, which means “of the womb” in Latin, was a common diagnosis for many women who complained of pelvic pain. Pregnancy was considered a cure for dysmenorrhea (painful periods), and women with this complaint were typically encouraged to marry and get pregnant as soon as possible. In cases where ancient doctors did recognize endometriosis symptoms such as pelvic adhesions (fibrous scarring that connects organs or tissues, causing pain), they prescribed preparations containing the urine of men or bulls, tar water, castor oil, or the secretions of the blister beetle – either to be swallowed or inserted vaginally. Leeches were also a popular treatment for gynecological conditions.

In the 1920s, Canadian gynecologist Thomas Cullen first identified and described how endometrial implants are associated with disease activity. In the 1940s, new techniques in endoscopy allowed doctors to better examine and visualize what was happening inside the body in cases of endometriosis. 1960 brought the first birth control pill, and the age of hormonal treatment for endometriosis began. Treatment for endometriosis further improved in the 1970s, when laparoscopic surgical techniques gained acceptance. Laparoscopic removal of implants and adhesions lowered the risk for surgery-related complications and made for much faster healing.

Modern research into endometriosis is focusing on new and better treatments and possible ways to prevent the condition from developing.

How common is endometriosis?

Approximately 176 million women worldwide are impacted by endometriosis, and an estimated one out of 10 women suffer from the disease in the United States. It is impossible to know how many women remain undiagnosed. Endometriosis mostly affects women in their reproductive years, especially between the ages of 25 and 40, but can develop in girls as young as 11.

One study estimates that 75 percent of women who experience pelvic pain and 50 percent of women with fertility issues have endometriosis.

What are the stages of endometriosis?

There are four stages of endometriosis: minimal, mild, moderate, and severe. Stage is determined by location, amount, depth, and size of the endometrial implants.

The stage of endometriosis is not necessarily related to level of pain experienced. In other words, someone with stage 1 endometriosis may experience significantly more pain than someone with stage 4 disease. Read more about the stages of endometriosis.


Can I get pregnant if I have endometriosis?

Many women with endometriosis do get pregnant. However, women with endometriosis may find it harder to get pregnant. In fact, researchers think endometriosis may affect as many as one in every two women with infertility.

Some possible reasons for infertility include:

  • Endometrial growths block off or alter the shape of the pelvis and reproductive organs. This can make it harder for the sperm to find the egg.
  • The immune system, which normally helps defend the body against disease, attacks the embryo.
  • The endometrium does not develop as it should, making it difficult for an embryo to implant in the womb.

Additionally, some treatments for endometriosis may delay or prevent pregnancy. Read more about endometriosis treatment options.

Is there a connection between endometriosis and endometrial cancer?

Endometriosis and endometrial cancer are separate conditions. Both cause pelvic pain. Research indicates that women diagnosed with endometriosis may have a slightly higher risk for developing endometrial cancer in later in life than women who do not, but it is unclear how much the risk is increased. The average lifetime risk for any woman to develop uterine cancer (of which endometrial cancer is one type) is 2.8 percent. Like most cancers, the development of endometrial cancer depends on many factors. Having endometriosis does not necessarily mean you are at a higher risk of getting cancer than someone who does not have endometriosis.

How is endometriosis diagnosed?

Typically, a gynecologist or other health care provider will review a patient’s medical history and complete a physical examination and pelvic exam. A diagnosis of endometriosis can only be confirmed after the doctor performs a laparoscopy and biopsies tissue. Other examinations that may be used in the diagnosis of endometriosis include ultrasound, computed tomography (CT) scan, and magnetic resonance imaging (MRI) scan. But laparoscopy is considered the gold standard for diagnosis of endometriosis. Read more about endometriosis diagnosis.

What are the symptoms of endometriosis?

Symptoms of endometriosis may include excessive menstrual cramps, back pain, abnormal or heavy menstrual flow, pain during intercourse, chronic fatigue, infertility, painful bowel movements or urination, bloating, and gastrointestinal issues like nausea, diarrhea, or constipation. Learn more about endometriosis symptoms.

How is endometriosis treated?

Depending on severity of the symptoms, treatment for endometriosis may include pain medications (ranging from over-the-counter to prescription), hormonal therapy (such as oral contraceptives), or surgery (laparoscopy, laparotomy, or hysterectomy). Read more about endometriosis treatments.

Endometriosis vs. adenomyosis

While symptoms can be similar, the underlying root cause is different. Endometriosis develops outside of the uterus. Adenomyosis is limited to the inside of the uterus. A notable difference is that adenomyosis symptoms most often start late in the childbearing years after having children. Read more about the differences between endometriosis and adenomyosis.


External resources

MyEndometriosisTeam resources

Kelly leads the creation of content that educates and empowers people with chronic illnesses. Learn more about her here.

A MyEndometriosisTeam Member said:

Reasons why more research/ risk assessment is important one of my friends ended up with Endometrial Cancer in her 40's along with having Endometriosis.… read more

posted 27 days ago

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