About Endometriosis

For you or a loved one with endometriosis, this section goes into the medical treatment methods and alternative therapies available. Perhaps most importantly, though, it emphasizes the importance of a support network and empowers people with practical things they can do to make it easier to live with the condition.

What is Endometriosis?

Endometriosis is a chronic and relapsing condition where endometrial-like tissue, which normally lines the inside of the uterus only, is found outside of the uterus. Often it affects ovaries, fallopian tubes, outer surface of the uterus, bladder, bowelrectum, ureters and ligaments. In more rare cases, it has been found outside the pelvis and abdomen in areas such as the lungs, brain, skin, arm and thigh.

The clumps of endometrial-like tissue that grow outside the uterus may be called lesions, nodules, cysts, growths or implants. They are most often found on the ovaries, the fallopian tubes, the outer walls of the uterus, the intestines and other organs in the belly. The clumps can cause pain, internal scarring, and formation of adhesions (bands of scar tissue that can connect organs inappropriately).

Endometriosis is NOT a cancerous condition and can be managed successfully by several methods.

Your menstrual cycle and endometriosis

In most women, the menstrual cycle is about every 28 days. Each month, the brain sends signals to your ovaries to produce sex hormones called estrogen and progesterone, which stimulate ovulation. During the first weeks of each cycle, the membrane lining inside the uterus thickens and grows. If there is no pregnancy, this membrane is eliminated as normal menstrual flow.

In those who are affected by endometriosis, the endometrial-like tissue (lesions) outside your uterus responds to changes in estrogen, an important female hormone. The lesions act like the tissue lining your uterus; they grow, breakdown and bleed like the uterine lining does during the menstrual cycle. This repetitive monthly breakdown and bleeding can eventually cause inflammation and scarring which can cause pain, especially before and during menstruation. Some women experience pelvic and abdominal pain (not associated with their menstrual cycles) which occurs on a daily basis and may last for six months or longer.

Endometriosis lesions can vary in colour and shape. They may be as small as grains of sand or as large as a grapefruit.

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What causes Endometriosis?

Causes of endometriosis

While the exact cause of this condition is unknown, there are several theories:

  • Menstrual blood carrying endometrial cells may stream against the menstrual flow back through the fallopian tubes and empty into the pelvic cavity.
  • Lesions can appear if the immune system is not sufficiently active to prevent them from growing and spreading.
  • Endometrial cells can circulate in the blood system or lymph vessels and be delivered into the pelvic cavity.
  • Some types of cells in your abdomen may react to hormones by transforming into endometrial cells.
  • Some women may carry genes that make them more likely to develop endometriosis; research has found that the chance of developing endometriosis is 15% higher for a woman whose mother has the disease.
  • Endometriosis may occur as a result of endometrial cells being directly transplanted into an incision during surgery, such as a C-section.

Endometriosis and the role of hormones

While the cause of endometriosis is not known, experts have observed that estrogen hormones make endometriosis worse. Women who are of childbearing age—from their teens into their 40s—have high levels of estrogen. Since endometriosis is an estrogen-dependent condition, it is during these years that women can develop endometriosis.

The hypothalamus, a gland in your brain, secretes a hormone called GnRH, or gonadotropin-releasing hormone.

GnRH signals the pituitary gland, another gland in your brain, to release hormones called LH (luteinizing hormone) and FSH (follicle stimulating hormone).

LH and FSH stimulate your ovaries to produce estrogen and progesterone, which acts on your endometrial tissue.

When women reach menopause (a point in time 12 months after the last menstruation), estrogen hormone levels drop and periods end for good. The symptoms of endometriosis tend to decrease when women enter menopause.

Fast facts

  • The word “endometriosis” comes from “endometrium,” which is the tissue that lines the uterus.1
  • Endometriosis is a chronic and relapsing condition where endometrial-like tissue is found outside of the uterus.2,3
  • The misplaced endometrial-like tissue acts like the tissue lining the uterus does during the menstrual cycle. Each month the tissue builds up, breaks down and sheds. However, unlike menstrual blood, the blood and tissue from endometriosis have no way of leaving the body. The resulting inflammation and possible scarring (adhesions) can lead to the painful symptoms of endometriosis and may contribute to infertility.2
  • Endometriosis usually affects the pelvic area including the ovaries, fallopian tubes, and outer surface of the uterus, as well as the vagina, cervix, vulva, bowel, bladder and rectum.3
  • Endometriosis is relatively common, affecting up to 10% of women of reproductive age.3,4
  • The most common symptom of endometriosis is pain. The types of pain include severe menstrual cramps, pelvic pain, pain during sex, intestinal pain, painful bowel movements and pain during urination which can occur during and between menstrual periods.3,5
  • Women with endometriosis may find it more difficult to get pregnant because scar tissue can block the fallopian tubes making it hard for the egg and sperm to meet. However, many women with endometriosis can get pregnant, it just may take longer.5,6
  • Endometriosis has been reported in 25% to 50% of women who suffer from infertility compared with 5% in fertile women.4


  1. John Hopkins Medicine. Endometriosis.
  2. The Society of Obstetricians and Gynaecologists of Canada (SOGC). What is endometriosis?
  3. US Department of Health and Human Services (DHHS). Office on Women’s Health. Endometriosis.
  4. SOGC. Endometriosis: Diagnosis and Management [Guidelines]. Journal of Obstetrics and Gynaecology Canada (JOGC) 2010;32(7)suppl 2:S1-S32.
  5. SOGC. What are the symptoms of endometriosis?
  6. SOGC. Do you know the facts? Learn about endometriosis, its symptoms and available treatments.

Are there other associated conditions?

If you have endometriosis, you may also develop certain other conditions, such as:

  • Impaired fertility: About one-third to one-half of women with endometriosis have difficulty getting pregnant. Because it can become harder to get pregnant the longer a woman has endometriosis, doctors may advise not to delay pregnancy.
  • Adhesions: Adhesions are abnormal bands of fibrous tissue that can cause pelvic tissues and organs to stick to each other. These can be treated with surgery but may reappear.
  • Ovarian cysts: These are fluid-filled cysts in the ovaries that may become very large and painful. These can also be treated with surgery but may reappear.
  • Cancer: Some studies suggest that endometriosis increases the risk of ovarian cancer. Another type of cancer called endometriosis-associated adenocarcinoma, in rare instances, can develop later in women who have had endometriosis.

If you are living with any of these associated conditions, your gynaecologist or family doctor may refer you to other specialists such as oncologists or centres such as fertility clinics for the help they can give you with their respective expertise.

What are the effects of Endometriosis?

Common symptoms

Although symptoms may change over time, if you have endometriosis, you probably have experienced one or more of the following symptoms:

  • Severe menstrual cramps and associated pain (can start a few days before your period and last throughout your period)
  • Pelvic pain
  • Pain during sex
  • Lower back and abdominal pain
  • Tiredness
  • Heavy or irregular bleeding
  • Painful urination and/or bowel movements
  • The following may occur during menstrual periods:
    • Diarrhea
    • Constipation
    • Bloating
    • Nausea
  • Difficulty conceiving

Endometriosis can cause intense cyclic or constant pelvic or lower abdominal pain that interferes with your normal daily activities, as well as health and well-being.

To help you report all symptoms to your doctor, fill out this questionnaire and take it to your next appointment.

Your symptoms

Every woman has symptoms that are unique to her situation. They may get worse during monthly periods or appear in the middle of each cycle.

Answer Yes or No to the following questions:

Cramps Yes No
  • Do you have to limit your normal activities each month due to painful periods?
  • Are your cramps becoming more painful with each passing year?
  • When do your cramps occur?
  • Are your cramps very severe?
  • When you have cramps, do you also experience nausea, vomiting or intestinal problems (e.g., constipation or diarrhea)?
Pelvic pain Yes No
  • Do certain movements or positions cause pelvic pain?
  • Do you have lower back pain before or during your periods?
  • Do you have pain when you urinate (pee) or when you defecate (poop)?
Pain during sex Yes No
  • Do you avoid having sex because of pain?
  • Do you feel deep-seated pain in your vagina during sex?
  • Is having sex more painful at certain times of the month or in certain positions?

Which body parts are affected?


Endometriosis usually occurs in the following sites in your body:

  • Ovaries
  • Fallopian tubes
  • Ligaments that support the uterus (called uterosacral ligaments)
  • Space between the uterus and rectum (called posterior cul-de-sac)
  • Space between the uterus and bladder (called anterior cul-de-sac)
  • Outer surface of the uterus
  • Pelvic cavity lining

At times, endometrial-like tissue may also be found elsewhere in the body, such as:

  • Intestines
  • Rectum
  • Bladder
  • Vagina
  • Cervix
  • Vulva
  • Scars due to abdominal surgery

Image source: hopkinsmedicine.org

Your healthcare professional can use laparoscopy to assess the stage of your endometriosis. These stages may be important to plan your treatment and monitor your progress.

Stages are classified as follows: minimal (Stage I), mild (Stage II), moderate (Stage III), or severe (Stage IV).

Several factors are considered during staging, including the number, size and location of lesions. The stage also depends upon the surface area affected and on how close the lesions are to other organs.

It’s important to keep in mind that the stage of the endometriosis is not an indicator of the level of pain experienced, risk of infertility or even symptoms present. It is possible for a woman in stage 1 to be in tremendous pain, while a woman in stage 4 may have no symptoms at all.

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How to prepare

Support means everything


No man is an island: in other words, you don’t have to live with endometriosis by yourself. Your friends and family can help, along with your treatment team of health care professionals.

Living with any chronic disease can make you feel isolated and sad; especially when you have to adapt or change your daily routine, see many health care practitioners, and learn medical terms. But you don’t need to do it alone.

When you’re living with endometriosis, it’s invaluable to keep the lines of communication open with your family, friends and coworkers: they can’t understand what it’s like to live with endometriosis if you don’t talk openly about it.

Here are some tips and helpful insights we’ve learned from Endometriosis patients:

  • Ask those closest to you to learn about your condition. This way they’ll understand your symptoms, or even go with you to your appointments. They can read this or other web sites, or consult reliable sources like libraries, or refer to our resources section.
  • Let them know you need their support. This could be just a sympathetic ear when you need to talk. Be sure to tell them that some diseases can have good and bad days.
  • Always be open and honest about your endometriosis. It’s the only way people can help you. Remember, if you’ve ever said to a friend or family member, “You don’t know what it’s like”, that’s maybe because you haven’t told them.

When we stop doing the things we love, our mood drops, symptoms seem worse, and it becomes even harder to get motivated. Keeping fun in your life is absolutely essential — make it a top priority. It boosts your mood, your relationships, and your energy level. Find one activity you love — even a small one — that you can add to each week without fail, and one you can add to each day. Once they become routine, you'll start feeling better and will want to add more.

Endometriosis is different for every patient, and treatment must be tailored for each individual case. The key is to communicate regularly with your doctor about your progress and the effects of your treatment, and to follow your treatment instructions every day, as medication can take time to work. If you feel there’s a problem with your regimen, or are experiencing any side effects, talk to your doctor right away about trying alternative methods. Don't hesitate to ask questions and get involved in decision-making regarding your health. And keep in mind there are many options available to you, so if one approach isn’t working, another one might.

There are independent patient associations and organizations that may be able to help you learn more.

Learn more

Lifestyle options

Lifestyle options

If you have endometriosis, talk to your health care professional for more guidance. While there’s no cure yet for endometriosis, a healthy lifestyle certainly supports overall health.

Tip: use a medical diary to record the pain and other symptoms you have experienced. Recording the time, length, severity and type of symptoms will help you identify patterns. Knowing these patterns can help you predict when you are likely to experience pain, which can make it easier to cope. A diary can also help during visits with your doctor. Several types of diaries that can be filled in are available free online (web or app).

Regular exercise can help women who suffer pain due to endometriosis. The body produces chemicals called endorphins during exercise. These endorphins can help reduce pain.

Some doctors recommend tai chi, yoga, mindfulness techniques and meditation to help manage pain. Scientists also suggest that a regular routine of running, biking, swimming or other aerobic activity, may help to decrease period pain.

A healthy diet based on Canada’s Food Guide is recommended for most people.

Endometriosis can lead to inflammation which can cause pelvic pain. Eating an “anti-inflammatory diet” may help reduce pelvic pain.

For women with endometriosis, these measures have been recommended:

  • Eating “anti-inflammatory” foods such as Omega-3 fatty acids (found in many types of fish) as well as legumes, nuts, seeds, and avocados.
  • Reducing the amount of red meat eaten since environmental dioxins and PCBs are often stored in animal fat.
  • Avoiding sugar and refined carbohydrates since these types of foods may contribute to inflammation.
  • Since dairy products increase the production of prostaglandins which can cause pain, some doctors recommend minimizing dairy.

Maintaining a healthy weight is also important. Women who are overweight produce more estrogen which can increase pain. It’s also important to drink enough fluids and eat fibre-containing foods to keep your bowels regular and avoid constipation.

Here are a couple of ways you can use heat to ease the pain of endometriosis:

  • Take warm baths
  • Use a hot water bottle or heating pad on your abdomen

Approximately 60% of women with endometriosis experience pain during sex. This pain can vary with the menstrual cycle so it’s a good idea to keep a diary of your pain levels and try to have sex when the pain is less severe. This may be just after your period but it can vary.

Experiment with different sexual positions. Since deep penetration is often the cause of pain, positions with less penetration may help. For more information about coping with painful sex, visit Women's Health Matters.

Complementary therapy options

For some people with endometriosis, complementary and alternative therapies — treatments that fall outside the scope of traditional western medicine — are an option that can be considered. Ask your health care professional about alternative therapies.

Some endometriosis-related pelvic pain may be related to joint or muscle problems. A physiotherapy screening assessment can help identify this type of pain.

Physiotherapy treatment may involve: education, manual therapy, stretching, and relaxation, strengthening or coordination exercises and behavioural modification (e.g., for urinary issues).

Some women have reported relief from pain after acupuncture treatment. In a few small studies, scientists have discovered that acupuncture reduces the pain of endometriosis.Thirty minutes of acupuncture have been reported to help reduce menstrual problems and improve fertility.

Certain herbs that are prepared as a boiled decoction, as dried herbal extracts, or taken as pills or capsules have been used to treat endometriosis. These herbal products may help improve bleeding problems, shrink lesions, improve fertility and reduce the rate of endometriosis reoccurrence.

Other alternative therapies include:

  • Traditional Chinese medicine
  • Homeopathy
  • Allergy management
  • Immune therapy

Medical treatment

Formal diagnosis of endometriosis may require laparoscopy and histology. Laparoscopy involves a lighted viewing instrument called a laparoscope being inserted through one or more small incisions. The surgeon uses this technique to look for signs of endometriosis and other problems.

Histology involves using a microscope to assess tissue. However, in Canada, a formal diagnosis of endometriosis is not necessary prior to starting medical treatment for endometriosis.

It is important to keep in mind that even if a laparoscopy assessment comes back negative, you may still have endometriosis. Furthermore, diagnostic laparoscopy is not required before treatment of endometriosis if pelvic pain is the problem.

Your doctor will recommend treatment based on your medical history (e.g., family history of endometriosis, symptoms, medications you are taking and reproductive health such as menstrual cycle regularity and pregnancies), physical exams (e.g., pelvic exams), as well as imaging tests such as ultrasound, colonoscopy or magnetic resonance imaging (MRI).

Your doctor has a range of different prescription and surgical treatment options to choose from. These are described in this section.

Over-the-counter medications such as Tylenol or Advil can be used to control pain. These medications are inexpensive and non-addictive.

Hormone-based medications can be used to treat endometriosis. These may include:

  • Combined hormonal contraception (CHC)
  • Progesterone-based medications
  • Danazol
  • GnRH agonists with 'add-back' therapy (low doses of estrogen and/or progestin)
  • GnRH receptor antagonists

If you are not trying to get pregnant, hormonal birth control is generally the first step in endometriosis treatment. Hormonal birth control helps stop ovulation and the growing and shedding endometrial tissue each month. Therefore, pain and bleeding can be reduced or eliminated.

CHC includes the “pill”, “patch” or “ring”. CHC includes the hormones progestin and estrogen and can be taken continually, without the usual seven-day break each month. Continuous CHC can prevent menstruation and therefore may be a useful option for women who experience the most severe symptoms during their period.

Possible side effects of CHC include:

  • Headache
  • Nausea
  • Breast tenderness
  • Irregular bleeding or spotting
  • Blood clots
  • High blood pressure
  • Enlarged uterus
  • Hair loss

Please consult your healthcare professional regarding other possible adverse events with combined hormone-based therapy.

Progestin therapy has been used for birth control and can be used to relieve endometriosis pain. It is available in pill form or as an injection. Progestin treatments commonly prescribed in Canada include: oral dienogest, oral norethindrone acetate and injected DMPA (depot medroxyprogesterone acetate).

This therapy can be a good option for women with endometriosis who have had a hysterectomy.

Progestin therapy helps to lessen the effects of the estrogen that stimulates endometriotic growth in your body. Progestin usually stops ovulation and can shrink endometrial tissues.

Lifestyle options

With injection-based progestin therapy there can be a delay between when therapy is stopped and when ovulation resumes. For this reason, it may not be the best option if you are planning to get pregnant in the near future.

Progestin therapy may be associated with irregular breakthrough bleeding (bleeding that occurs between periods). Break-through bleeding may be particularly prolonged and heavy with injections. Other side effects include nausea, weight gain, breast tenderness, fluid retention and depression.

Please consult your healthcare professional regarding other possible adverse events with progestin-based therapy.

The IUS is an effective birth control method that consists of a T-shaped medicated intrauterine contraceptive device which is placed into your uterus. The medication in the IUS is the hormone progestin. An IUS can lessen pain caused by endometriosis.

The device releases a type of progestin hormone (levonorgestrel) which counteracts the effects of estrogen. The IUS can provide continuous therapy for up to five years or until it is removed by a healthcare professional.

Side effects include:

  • Irregular bleeding or spotting
  • Pain
  • Pelvic infection
  • Hormonal side effects, such as:
    • Headaches
    • Acne
    • Altered mood
    • Breast tenderness

Please consult your healthcare professional regarding other possible adverse events with the IUS.

A GnRH agonist (or gonadotropin-releasing hormone agonist) is a hormone, given by injection or nasal spray. It will cause you to stop menstruating. This effect helps reduce the pain associated with endometriosis and minimize endometrial lesions.

Treatment with a GnRH agonist decreases estrogen levels to levels seen after menopause.

The side effects of this type of medication tend to be similar to symptoms you might experience in menopause:

  • Loss of bone mineral density (BMD)
  • Hot flushes
  • Mood swings
  • Vaginal dryness
  • Headaches

These symptoms can be relieved with ‘add-back therapy’, which consists of low doses of estrogen and/or progestin. Add-back therapy is routinely given when a GnRH agonist is prescribed.

Please consult your healthcare professional regarding other possible adverse events with GnRH agonists.

A GnRH receptor antagonist (or gonadotropin-releasing hormone receptor antagonist) oral therapy is used to help treat the painful symptoms related to endometriosis, such as pain during or between periods, and pain or discomfort in the belly or pelvic region.

GnRH receptor antagonist therapy works to lower the amount of estrogen in your body partially or almost completely, depending on the dose used. Each individual plan will be unique based on their need and symptoms. This therapy often helps to reduce the painful symptoms of endometriosis after one to three months.

The most common side effects that may occur with this type of medication are:

  • Hot flush
  • Headache
  • Feeling sick to your stomach (nausea)

Other side effects that may also occur include dizziness, diarrhea, stomach pain, constipation, weight increase, difficulty sleeping, anxiety, depression, irritability, mood swings, decreased sex drive (libido), runny, stuffy nose, sore throat, sinus infection, common cold, joint pain, loss of bone mineral density and menstrual bleeding changes.

Please consult your healthcare professional regarding other possible adverse events with GnRH receptor antagonists.

Danazol is a hormone that is taken orally which causes you to stop menstruating and is effective in relieving the pain of endometriosis.

Danazol is a weak male hormone that lowers the level of estrogen and progesterone in a woman’s body.

Side effects of danazol include:

  • Weight gain
  • Acne
  • Excessive hair growth
  • Raised cholesterol levels
  • Breast atrophy

Due to these side effects, which can be common and serious, the drug is not widely prescribed. It is generally only used for a limited period of time.

Please consult your healthcare professional regarding other possible adverse events with danazol.

In some cases, surgery is advised to treat endometriosis. The procedure can vary greatly, from minor surgery to complete removal of all reproductive organs. Your healthcare professional will discuss the choices for surgery and their effects on fertility. Your age, severity of endometriosis, and the desire to bear children are important factors to consider in deciding if a surgical option is appropriate or, if it is, which surgical option is best for you. With surgery, symptoms typically recur within 2 to 5 years, unless it’s a total hysterectomy with bilateral salpingo-oophorectomy (BSO).

A laparoscope is used for both the diagnosis and treatment of endometriosis. Guided by a video image and using tiny instruments, the physician can remove the lesions. Laparoscopy is considered to be the preferred route for surgical management of endometriosis.

Laparoscopy requires only a few tiny abdominal incisions, which limits the amount of bleeding, scarring and post-operative pain.

Performed by a gynecologist or surgeon, laparoscopy is usually done under general anesthesia; however, local or spinal anesthetic are also options.

Complications from the surgery are rare, but can include:

  • Pelvic infection
  • Uncontrolled bleeding which means a larger abdominal incision (laparotomy) is required to stop the bleeding
  • Scar tissue formation
  • Damage to the bowel, bladder, or the small tubes that carry urine from the kidneys to the bladder (ureters)

Laparoscopy is often performed as an outpatient procedure. After returning home, you should be able to return to your normal activities after a week or so.

In some situations, a laparotomy is done. Laparotomy involves making a much larger incision in the abdomen than in laparoscopy and is considered to be a more extensive surgery.

Surgery to remove the uterus (hysterectomy) and ovaries (oophorectomy) used to be considered the most effective treatment for endometriosis. Doctors are now moving away from these approaches and instead focus on removal of all endometriosis tissue.

However, in advanced stages of endometriosis, when all other medical and less invasive surgical remedies have been tried and failed, the removal of the uterus with or without the ovaries may be the only treatment that relieves the patient’s symptoms.

In some cases, when endometrial damage is severe and fertility is not a concern, a hysterectomy, involving removal of the uterus, may be needed. Removal of the ovaries is only done when absolutely necessary since this results in menopause.

A hysterectomy and removal of both ovaries is considered to be the most aggressive form of treatment for endometriosis and is only considered as a last resort.


Please note that the information on this Web site should not be used as a substitute for seeking medical advice or treatment from a physician. You should not use this information to diagnose or treat a medical condition or health problem. Speak to your health care provider if you have any questions about your medical condition, symptoms or treatment options.




The SOGC website “Your Period” provides comprehensive information about topics related to menstruation including a section about endometriosis.

Endometriosis Network Canada

Volunteer-run, incorporated and not-for-profit, this organization aims to facilitate and promote patient-centred management of endometriosis.

Johns Hopkins Medicine

The mission of Johns Hopkins Medicine is to improve community health locally and globally by setting standards of excellence in medical education, research and clinical care.


A global platform that supports collaboration and information sharing between women with endometriosis, as well as among physicians, scientists, and others.

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