What is endometriosis?

Endometriosis is the presence of cells that line the uterus in other places in the abdomen. Endometrial cells are sometimes even found in the lungs.

Endometriosis is a disorder of the female reproductive system in which endometrial tissue (the normal lining of the uterus) is found outside the uterine cavity. An estimated three to five million American women of reproductive age suffer from endometriosis. This disease is prevalent in women 30-40 years of age, though it can begin in the late teens and early twenties. About 40 percent of patients with endometriosis will experience some degree of infertility.

Dr. Mehmet Oz, MD
Cardiologist (Heart Specialist)

If your cramps are very severe or disabling, it could be a sign of something more serious, such as endometriosis, a condition that can affect up to 10 percent of women. Endometriosis means that you may have uterine tissue growing outside the uterus, typically in the pelvic area, a situation that can cause severe cramps and pain.

Endometriosis describes endometrial tissue growing outside of the uterus, swelling and contracting on a monthly cycle. It is a cause of major pelvic pain—that is, pain in the pelvis or lower abdomen—and needs to be diagnosed by a doctor highly experienced in pediatric and adolescent gynecology, as it can look slightly different in younger teens than it does in women in their twenties or thirties.

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Dr. Jennifer A. Kalich, MD
OBGYN (Obstetrician & Gynecologist)

Endometriosis occurs when tissue lining the uterus (endometrium) is growing outside the uterus. Endometriosis often results in painful menstrual cycles. And, while the cause is unknown, endometriosis is found in approximately 35 percent of infertile women. A laparoscopy to evaluate for endometriosis and/or adhesions as a cause for infertility may be recommended.

Endometriosis is the implantation of endometrial tissue, which is the inner layer of the uterus, in sites outside the uterus. It most commonly occurs in the pelvis but can be nearly anywhere in the body. It is very common, benign and chronic, and is completely related to the natural surges of estrogen in the body.

Endometriosis causes inflammation and bleeding of the endometrium in different parts of your body. The endometrium is located in the uterus as an inner lining. During menstruation, the endometrial lining is shed along with blood. In an individual with endometriosis, the endometrial tissue is found in other parts of the body, like the fallopian tubes, lining in the pelvic cavity, or the ovaries, and continues to swell and bleed during menstruation. Its misplacement can cause heavy bleeding and pain.

Endometriosis is a chronic recurrent condition in which women suffer from various combinations of severe menstrual pain, pain on intercourse and chronic pelvic pain. Endometriosis may also cause infertility. Endometriosis is usually found inside the peritoneal cavity at the top of the vagina, other locations are also common and cysts filled with thick, deep brown fluid called endometriomas or chocolate cysts can be located in the ovary. Scar tissue can also form as a result of irritation and inflammation from the endometriosis.

Endometriosis occurs when the tissue that’s just supposed to line the uterus grows outside the uterus. It can be very painful.

During a woman’s menstrual period, vaginal blood and tissue flow out of her body. If a woman has endometriosis, that tissue that’s outside her uterus breaks down too. It has nowhere to go, so it just stays in the body. The result is often internal bleeding, pelvic pain, inflammation and trouble going to the bathroom.

Patricia Geraghty, NP
Women's Health

The endometrium is the lining of the uterus. Changes in hormones cause the lining to grow and shed with each menstrual cycle. The shedded lining is menstrual bleeding.

Endometriosis is when the specialized cells of the endometrium are located outside the uterus. These cells may be found in the tubes, around the ovaries, or in the abdomen. The cells respond to the hormone changes each month, growing and bleeding. This causes an inflammation that is painful and can eventually cause internal scarring. The woman with endometriosis has heavy and painful periods. After many years, she may have chronic pain in her lower abdomen.

Endometriosis runs in families. If a woman has endometriosis, her sister is five times more likely to also have it.

Dr. Madeleine M. Castellanos, MD
Psychiatrist (Therapist)

Endometriosis is a condition found in women in which pieces of tissue that are similar to the endometrium (inside lining of the uterus) are found in and around the abdominal cavity. These pieces of endometrial tissue respond to the monthly hormones that are secreted so that, when a woman has her menstrual period, these tissues also bleed. Since the body considers blood inside the abdomen an irritant, it tries to wall off the endometrial tissue by forming scar tissue around it. Every monthly cycle brings on more and more scar tissue. This scar tissue builds on itself and can actually adhere different organs together, such as the ovary to the intestine, or the uterus to the bladder.

Scar tissue is what is responsible for the symptoms and the infertility associated with endometriosis. Since scar tissue has no elastic fibers in it, it does not stretch like the other tissues or skin of the body. Because of this, when a woman has any type of movement, the organs and tissues of the abdomen and pelvis accommodate themselves accordingly, but the scar tissue stays firm. It causes tugging and tension of whatever tissues or organs it happens to be stuck to. This results in pain for some women when they are playing sports, or just bending over.

Endometriosis is a noncancerous condition in which tissue similar to the endometrium (uterine lining) grows outside your uterus and adheres to other structures, most commonly in the pelvis, such as on the ovaries, bowel, fallopian tubes or bladder. Rarely it implants in other places, such as the liver, lungs, diaphragm and surgical sites.

When endometriosis tissue grows outside of the uterus, it continues to respond to hormonal signals—specifically estrogen—from the ovaries telling it to grow. Estrogen is the hormone that causes your uterine lining to thicken each month. When estrogen levels drop, the lining is expelled from the uterus, resulting in menstrual flow (you get your period). But unlike the tissue lining the uterus, which leaves your body during menstruation, endometriosis tissue is essentially trapped.

With no place to go, the tissue bleeds internally. Your body reacts to the internal bleeding with inflammation, a process that can lead to the formation of scar tissue (adhesions). This inflammation and the resulting scar tissue may cause pain and other symptoms.

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Important: This content reflects information from various individuals and organizations and may offer alternative or opposing points of view. It should not be used for medical advice, diagnosis or treatment. As always, you should consult with your healthcare provider about your specific health needs.