Endometriosis risk factors: who is more likely to get it

What endometriosis is

The tissue that lines the inside of the uterus is called the endometrium. In endometriosis, tissue similar to that lining grows in other places in the body (NICHD). These patches are called implants, nodules or lesions. They are most often found on or under the ovaries, on the fallopian tubes, behind the uterus, on the tissues that hold the uterus in place and on the bowels or bladder. In rare cases they grow on the lungs or in other parts of the body (MedlinePlus).

The growths are benign (not cancer), but they can still cause problems such as pain, cysts on the ovaries, scar tissue and trouble getting pregnant (OWH). Researchers think that at least 11% of women, more than 6.5 million women in the United States, have endometriosis (OWH).

Who is more likely to get endometriosis

Endometriosis can affect anyone who menstruates (MedlinePlus). OWH says it is more common in women in their 30s and 40s (OWH). MedlinePlus lists these factors that raise the risk (MedlinePlus):

• a mother, sister or daughter with endometriosis;
• periods that started before age 11;
• short monthly cycles (less than 27 days);
• heavy periods that last more than 7 days.

OWH gives a similar list. It adds never having had children and a health problem that blocks the normal flow of menstrual blood out of the body during a period, and it counts an aunt as a family member who matters. It describes short cycles as 27 days or fewer (OWH).

What may lower the risk

MedlinePlus says the risk is lower if you have been pregnant before, if your periods started late in adolescence, or if you breastfeed your babies (MedlinePlus).

OWH says you cannot prevent endometriosis, but you may lower your chances by keeping the level of the hormone estrogen in your body lower. Its suggestions are to ask your doctor about hormonal birth control with lower doses of estrogen, to exercise regularly (more than 4 hours a week), to avoid large amounts of alcohol and to avoid large amounts of caffeinated drinks (OWH).

What causes endometriosis

No one knows for sure (MedlinePlus). OWH lists the possible causes researchers are studying: retrograde menstrual flow (some tissue shed during a period flows back through the fallopian tubes into the pelvis), which it calls the most likely cause; genes, because endometriosis runs in families; immune system problems; the hormone estrogen, which appears to promote endometriosis; and abdominal surgery such as a C-section or hysterectomy, during which endometrial tissue could be moved by mistake (OWH). NICHD notes that these theories do not explain every case (NICHD).

Symptoms

The most common symptoms are pain and infertility (NICHD). Other common symptoms include (NICHD):

• painful or even debilitating menstrual cramps, which may get worse over time;
• pain during or after sex;
• pain in the intestine or lower abdomen;
• painful bowel movements or painful urination during periods;
• heavy periods;
• spotting or bleeding before or between periods;
• problems getting pregnant.

Some people also have digestive symptoms or fatigue (MedlinePlus). How bad the pain is does not match the number, location or size of the patches: some women with a few small patches have severe pain, while others with large patches have little pain (NICHD). If you have symptoms of endometriosis, talk with your doctor (OWH).

Common questions

How is endometriosis diagnosed?

Your provider will ask about your symptoms and medical history, do a pelvic exam and may order imaging tests. Surgery is the only way to know for sure; the most common surgery for diagnosis is a laparoscopy, which uses a thin tube with a camera inserted through a small cut near the belly button (MedlinePlus).

Can I get pregnant if I have endometriosis?

Yes. Many women with endometriosis get pregnant, but it may be harder. Researchers think endometriosis may affect as many as one in every two women with infertility (OWH).

Is endometriosis linked to other conditions?

OWH lists links with allergies, asthma and chemical sensitivities; autoimmune diseases such as multiple sclerosis, lupus and some types of hypothyroidism; chronic fatigue syndrome and fibromyalgia; and certain cancers, such as ovarian and breast cancer (OWH). A link does not mean one condition causes the other.

Does it go away after menopause?

For some women the pain gets milder after menopause. Hormone therapy taken for menopause symptoms may keep the pain and other symptoms going (NICHD).

Is there a cure?

There is no cure, but there are treatments for the symptoms, including pain relievers, hormone therapy and surgery to remove the patches. Treatments for infertility caused by endometriosis include laparoscopy to remove the patches and in vitro fertilization (MedlinePlus).

Is there an endometriosis risk calculator?

None of these NIH and OWH pages offers a risk score you can use at home, and surgery is the only way to confirm the diagnosis (MedlinePlus). If the risk factors or symptoms above fit you, tell your doctor.

Also see ovarian cancer risk factors, the ovarian cancer screening check, lupus risk factors, and PCOS risk factors.