Medically Reviewed By William C. Lloyd III, MD, FACS
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What is endometriosis?

Endometriosis, also referred to as “endo,” is the abnormal growth of endometrial, or uterine lining tissue in areas other than the uterine lining, such as on the ovaries, in the fallopian tubes, the pelvic lining, or on the intestines. Less commonly, endometriosis may develop at other distant locations anywhere in the body.

During a woman's regular menstrual cycle, this tissue builds up and is shed if she does not become pregnant. Women with endometriosis develop tissue that looks and acts like endometrial tissue outside the uterus, usually on other reproductive organs inside the pelvis or in the abdominal cavity. Each month, this misplaced tissue responds to the hormonal changes of the menstrual cycle by building up and breaking down just as the endometrium does, resulting in internal bleeding.

Unlike menstrual fluid from the uterus that is shed by the body, blood from the misplaced tissue has nowhere to go. This causes the tissues surrounding the endometriosis to become inflamed or swollen. This process can produce scar tissue around the area, which may develop into lesions or growths. In some cases, particularly when an ovary is involved, the blood can become embedded in the tissue where it is located. It may then form blood blisters that become surrounded by a fibrous cyst.

The cause of endometriosis is not completely understood, but it may be a result of endometrial cells going in the reverse direction, backing up through the fallopian tube and into the pelvis. It is also possible that factors related to the immune system play a role in its development or that endometrial tissue develops in abnormal locations in affected women.

This condition affects 10% of all premenopausal females and 25% of infertile women. Endometriosis is considered a major cause of female infertility. In mild to moderate cases, the infertility may be just temporary. In these cases, surgery to remove adhesions, cysts, and scar tissue can restore fertility. In a very small percentage, women may remain infertile.

Endometriosis is most common in women between the ages of 25 and 35. It also has a strong familial link. If your sister or mother has the condition, then you are approximately 5 to 6 times more likely to develop it.

The symptoms of endometriosis may occur frequently or not at all. Some women with endometriosis do not have symptoms, while others experience pain and prolonged vaginal bleeding during menstruation. The pain can be cyclical and can occur during sexual activity (dyspareunia). The symptoms may occur during menstruation or up to 10 days before or after a woman’s menstrual period.

Treatment options range from medications to surgical procedures. The severity of symptoms, location of the endometriosis, and age of the woman are considered when making the appropriate decision for treatment.

Seek immediate medical care (call 911) for serious symptoms, such as severe abdominal pain, persistent vomiting, or inability to urinate or have a bowel movement. Seek prompt medical care if you are being treated for endometriosis but mild symptoms recur or are persistent, or if you experience blood in the urine or difficulty urinating.

What are the symptoms of endometriosis?

Cyclical pain in the pelvic area is the most common symptom of endometriosis, but the severity of the pain does not relate to the amount of endometriosis that is present. The symptoms can vary in intensity among individuals.

Common symptoms of endometriosis

You may experience endometriosis symptoms daily or only occasionally. Any of the following symptoms can be severe:

  • Abdominal, pelvic, or lower back pain during and after menstrual period
  • Cramps in pelvis before, during and after menstrual period
  • Difficulty or inability to get pregnant (subfertility)
  • Lower back pain
  • Menstrual periods that are very painful
  • Pain during or after sexual intercourse
  • Painful bowel movements

Serious symptoms that might indicate a life-threatening condition

In some cases, endometriosis can be life threatening. Seek immediate medical care (call 911) if you, or someone you are with, have any of these life-threatening symptoms including:

  • Inability to have a bowel movement
  • Inability to urinate
  • Persistent vomiting
  • Severe abdominal pain

What are the stages of endometriosis?

Doctors classify endometriosis in four stages based on the amount, location, size and depth of the endometrial tissue. This can include how far the tissue has spread, which pelvic structures are affected, and whether the fallopian tubes are blocked.

The four stages of endometriosis are defined as:

  • Stage 1: Minimal
  • Stage 2: Mild
  • Stage 3: Moderate
  • Stage 4: Severe

The stage of endometriosis does not necessarily correlate to the severity of symptoms or risk of infertility. Someone with severe endometriosis might still have no symptoms, while a patient with mild, stage 1 endometriosis can experience intense pain. However, infertility is very likely in someone with stage 4 endometriosis.

What causes endometriosis?

Endometriosis develops in women when endometrial tissue grows in areas outside of the uterus. Like the uterine lining, this extra-uterine tissue responds to the hormonal changes of each menstrual cycle by swelling, thickening, and possibly bleeding. However, unlike the uterine lining, which is shed off each month, this abnormal endometrial tissue remains where it is located. Eventually, this extra-uterine tissue may scar, forming an adhesion that may be painful or cause more symptoms.

The precise cause of endometriosis is not entirely understood. There is no solid consensus as to how endometrial cells are able to reside outside of the uterus. Some researchers hypothesize that nests of stem cells were erroneously programmed during fetal development due to genetic or environmental factors. This misdirected endometrial tissue does not make itself known until puberty due to the influence of female hormones.

It is also possible that endometriosis could be due to the reverse movement of endometrial cells as they shed from the wall of the uterus during the normal menstrual cycle. Or, finally, endometriosis could be due to immune factors or to the development of new endometrial tissue in abnormal sites.

What are the risk factors for endometriosis?

A number of factors increase the risk of developing endometriosis. Not all people with risk factors will develop endometriosis. Risk factors include:

  • Blocked flow of menstrual blood during the period, possibly due to a closed hymen
  • Family history of endometriosis
  • Frequent menstrual cycles
  • Short menstrual cycles
  • Young age at start of menstruation

Reducing your risk of endometriosis

There is no way to definitively prevent endometriosis. However, you can take steps to reduce your likelihood of developing the condition if you have risk factors.

Because estrogen works to thicken the lining of your uterus during menstruation, lowering your estrogen level can help mitigate the risk of endometrial tissue forming outside the uterus.

You can lower your estrogen levels by:

  • Asking your doctor about hormonal birth control with lower doses of estrogen
  • Avoiding highly caffeinated drinks, such as green tea or soda, which can raise estrogen levels
  • Exercising regularly, which can also help lower your percentage of body fat, in turn decreasing the amount of estrogen moving through your body
  • Limiting alcohol to one drink per day, as heavy alcohol use can increase estrogen levels

What are some conditions related to endometriosis?

Adenomyosis is a condition similar to endometriosis, with similar symptoms. In endometriosis, endometrial tissue begins growing outside the uterus, potentially extending to the ovaries, cervix, fallopian tubes, or lower intestine. With adenomyosis, endometrial tissue begins growing into the muscle of the uterus itself, causing it to expand in size. This can lead to abnormal bleeding; heavy, painful periods; and painful sexual intercourse.

Because some of its symptoms mimic those of other conditions, endometriosis can sometimes be misdiagnosed or mistaken for other issues that cause pelvic pain, including ovarian cysts, pelvic inflammatory disease (PID), or irritable bowel syndrome (IBS).

Infertility, or impaired fertility, is a primary complication of endometriosis. About one-third to one-half of patients with endometriosis experience difficulty getting pregnant. However, treatment of early-stage endometriosis, including surgical removal of endometrial tissue, can be effective in improving fertility and allowing for successful pregnancies. In more advanced cases, additional fertility treatments may be needed. The good news is many people with endometriosis are able to conceive successfully and deliver healthy babies.

How do doctors diagnose endometriosis?

For many women, simply having a diagnosis of endometriosis brings relief. There is finally a recognized cause for their symptoms, and they can begin discussing effective treatment options.

Diagnosis begins with a gynecologist evaluating a patient's medical history and a complete physical examination including a pelvic exam. A diagnosis of endometriosis can only be certain when the physician performs a laparoscopy.

A laparoscopy is a minor surgical procedure in which a laparoscope (a thin tube with a lens and a light) is inserted into an incision in the abdominal wall. Using the laparoscope to see into the pelvic area, the physician can often determine the locations, extent, and size of the endometrial growths.

Other tests that may help in diagnosing endometriosis include:

  • Computed tomography (CT or CAT scan)
  • Ultrasound

How is endometriosis treated?

Some women with endometriosis never have any symptoms, but when symptoms do occur, there are several treatment options available. Your healthcare provider will determine the best treatment options for you based on your age, the severity of your symptoms, and whether or not you plan to have children.

Treatment options for endometriosis

A number of different treatment options for endometriosis are possible. The choice of treatment depends upon the severity of the condition, a woman’s desire for fertility, and the overall health and age of the patient. Options include:

  • Hormone medications, such as a gonadotropin-releasing hormone agonists and antagonists, oral contraceptives, or progestins to slow the growth of endometriosis and to reduce the size of endometriosis implants (growths or deposits of endometrial tissue)
  • Hysterectomy, the surgical removal of the uterus (partial hysterectomy) or the uterus and cervix (total hysterectomy)
  • Nonsteroidal pain medications, such as ibuprofen (Advil), acetaminophen (Tylenol), and naproxen (Aleve)
  • Surgical removal or destruction of endometriosis
  • Treatments for infertility, if indicated

Alternative therapies and at-home remedies for endometriosis symptoms

Finding an endometriosis treatment that works can take time, and you may continue to experience pain. Talk to your doctor about ways you can manage symptoms through alternative therapies and home treatments, including:

  • Acupuncture, which is not scientifically proven as a treatment for endometriosis pain, but has been reported by some patients as a way to find symptom relief
  • Cognitive behavioral therapy (CBT), a method of reframing thought patterns to cope with physical, mental and emotional challenges. More research is needed on the use of CBT for endometriosis pain specifically, but the therapy has been successful in treating other types of chronic pain.
  • Heating pad or warm baths, to ease cramping and pain
  • Pelvic floor physical therapy, in which a trained physical therapist guides the patient through a series of exercises and manipulations of the pelvic floor muscles to help alleviate tightness and pain
  • Stress management through healthy lifestyle habits, such as a nutritious diet, regular exercise, and good sleep habits, which can reduce sensitivity to pain and make it easier to cope with endometriosis symptoms
  • Support groups, either online or in person, where you can connect with other people living with endometriosis and share challenges, feelings, and coping tips

What are the diet and nutrition tips for endometriosis?

There has not been any scientific link found between endometriosis and diet. However, proper nutrition is one component of a healthy lifestyle—along with regular exercise, quality sleep, and stress management—which can help you reduce your risk of developing endometriosis or help manage symptoms.

Healthy diet tips for endometriosis include:

  • Avoiding alcohol and caffeine, both of which can increase estrogen levels, a contributing factor to endometriosis
  • Focusing on fresh fruits, vegetables and whole grains and avoiding processed foods
  • Limiting red meat in favor of lean poultry, fish, and plant-based proteins
  • Including healthy fats, such as those found in avocado, chia seeds, olive oil, and fatty fish like salmon

How does endometriosis affect quality of life?

Endometriosis can present a range of challenges, from the time when symptoms begin all the way through the treatment process. For many women, symptoms may be overlooked, mistaken by doctors for other conditions, or even dismissed by friends and family as not real.

Endometriosis and chronic pain

Even after diagnosis and through treatment, chronic pain can persist, causing persistent disruption to daily life. Work, school, social outings, and home life can all be affected negatively by the constant presence of endometriosis symptoms. Medications, alternative therapies, and other coping mechanisms can help manage pain. Talk to your doctor if your endometriosis symptoms are becoming overwhelming or impacting your ability to enjoy your typical routine.

Endometriosis and sex

For many, painful sexual intercourse is a first sign of endometriosis that leads to a diagnosis. Even with treatment, endometriosis can still make intimacy difficult. The chronic pain and stress of the condition can limit libido, and the physical act of intercourse can still be uncomfortable or painful.

Your doctor can discuss options for additional treatment to address symptoms that are affecting your sex life. You and your partner should talk honestly about how endometriosis might change the way you are intimate together. Planning sex around the time of your menstrual period may help reduce pain due to inflammation, or you may find other ways to be sexual that don’t involve vaginal penetration. Talking to a qualified sex therapist or counselor can also help you and your partner work together to find the type of intimacy that works best for you.

Endometriosis and infertility

For many with endometriosis, uncertainty about fertility is the first issue that comes to mind after diagnosis. In addition to the physical pain of endometriosis symptoms, the prospect of infertility can bring emotional stress as well. Patients who take hormone therapy may worry about the long-term effects on a potential pregnancy or unborn child. Those who wish to conceive may have difficulty and require additional fertility treatments, which in turn presents its own challenges. In cases of severe endometriosis, doctors may recommend a partial or complete hysterectomy for effective treatment, which means making the decision to become permanently infertile.

While endometriosis presents many difficulties, treatment options and coping therapies can help make symptoms manageable. You are not alone—5 million American women have endometriosis.

Talk to your doctor if the effects of endometriosis are disrupting any or all aspects of your daily life. Finding endometriosis support groups online or in person can also provide an outlet to connect with others like you who understand the emotions, fears and challenges of living with endometriosis.

What are the potential complications of endometriosis?

Infertility is the main complication of endometriosis. You can help minimize your risk of serious complications by following the treatment plan you and your healthcare professional design specifically for you.

Complications of endometriosis include:

  • Chronic pain
  • Gastrointestinal blockage
  • Hemorrhage
  • Infertility
  • Pelvic cysts that have the potential to rupture (endometriomas)
  • Perforation of affected organ
  • Urinary blockage
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Medical Reviewer: William C. Lloyd III, MD, FACS
Last Review Date: 2021 Mar 26
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THIS TOOL DOES NOT PROVIDE MEDICAL ADVICE. It is intended for informational purposes only. It is not a substitute for professional medical advice, diagnosis or treatment. Never ignore professional medical advice in seeking treatment because of something you have read on the site. If you think you may have a medical emergency, immediately call your doctor or dial 911.
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