Endometriosis

Endometriosis is a long-term condition in which tissue similar to the lining of the uterus grows in other places, most often on the ovaries, the outside of the uterus and the lining of the pelvis, and sometimes the bowel or bladder. That tissue responds to the menstrual cycle, which can cause inflammation, scarring and bands of tissue called adhesions. Pain and deep tiredness can be there between periods as well as during them.

What endometriosis is, and what it is not

It is not simply heavy period pain. Endometriosis affects the whole body, and many people have pelvic pain, bowel or bladder pain, nausea and fatigue on days when they are not bleeding at all. It is also not caused by anything a person did or failed to do, and it is not a reflection of how well someone copes with pain.

How many Canadians live with it is genuinely unclear. Health Canada states that endometriosis affects about 1 in 10 girls and women of reproductive age, alongside an unmeasured number of transgender, non-binary and gender-diverse people who have a uterus. Canada has no national surveillance for the condition, and published counts range from roughly half a million to about two million depending on the source, which is why this page uses the Health Canada proportion rather than a single number.

Signs and symptoms

• Period pain severe enough to interfere with school, work or daily activities
• Pelvic pain that continues between periods
• Pain during or after sex
• Pain with bowel movements or urination, often worse around a period
• Heavy or unpredictable menstrual bleeding
• Bloating, nausea and deep fatigue
• Difficulty becoming pregnant

Symptoms differ a great deal between people, and the amount of visible disease does not reliably match the amount of pain someone feels.

What raises the risk

The things linked to endometriosis are ones nobody can change:

• Having menstrual cycles, since the condition is driven by cyclical hormone activity
• A first-degree relative with endometriosis
• Starting periods at a young age
• Short menstrual cycles, or long and heavy periods
• Conditions that block menstrual flow leaving the uterus
• Never having been pregnant, which is linked to higher reported rates although the direction of that relationship is debated

There is no second list here. No modifiable cause of endometriosis has been established, so there is no diet, exercise pattern or habit that has been shown to bring the condition on. Some people do find that certain approaches help them manage symptoms, and that is a separate question from cause.

How endometriosis is diagnosed in Canada

Assessment begins with a detailed history of your pain, including where it is and where it sits in your cycle, along with a physical examination. Pelvic ultrasound and, in some centres, MRI can identify ovarian endometriomas and deep disease. Canadian practice has moved toward starting management on the basis of symptoms and imaging rather than waiting for surgery. Laparoscopy with tissue sampling can confirm the diagnosis and can also treat disease at the same time, but it is no longer required before care begins.

Diagnosis still takes a long time here. A joint brief to the House of Commons Standing Committee on Health reports an average of at least five years to a formal diagnosis in Canada, and the World Health Organization reports a global average of 4 to 12 years. The reasons described are structural rather than personal: symptoms overlap with several other conditions, awareness is uneven, and referral pathways to specialised care have gaps. Keeping a record of your symptoms and their timing gives a clinician the pattern they need to recognise it earlier.

Treatment and day-to-day management

Clinical research for Endometriosis is enrolling. See the current studies ↓

Care in Canada usually combines something for the pain, something to settle cyclical activity, and support for the parts of life the condition affects. Depending on your situation and what matters to you, a health care team may discuss:

• Combined hormonal contraception and progestin-only options, including oral, injectable, implant and intrauterine forms, used to suppress cyclical activity
• Gonadotropin-releasing hormone agonists and antagonists, generally with hormone add-back therapy
• Anti-inflammatory and other pain medicines for symptom management
• Laparoscopic surgery to remove or destroy endometriosis lesions and adhesions, in general gynaecology or specialised centres
• Multidisciplinary chronic pain care, including pelvic floor physiotherapy, psychological support and, where it applies, fertility care

What suits one person will not suit another. Which of these applies to you, if any, is a decision for you and your own clinician, and this page is not a recommendation about any of them.

When to talk to a doctor

• See a clinician if period pain regularly stops you from going to school or work, or if pain medication you can buy without a prescription is not enough.
• Book an appointment for pelvic pain between periods, pain during sex, or pain with bowel movements or urination, especially if it worsens around your period.
• Seek urgent care for sudden severe pelvic pain with fainting, fever or vomiting, or for heavy bleeding that soaks through a pad or tampon every hour for several hours.

Why clinical research matters for endometriosis

The cause of endometriosis is still unresolved, there is no blood test or other non-invasive marker that reliably identifies it, and the World Health Organization states that no cure currently exists. Canada also lacks national surveillance, standardised clinical pathways and a dedicated research funding stream, which is why the figures on this page come from Health Canada, advocacy briefs and international bodies rather than from Canadian health system data. Work now under way includes non-invasive diagnostic markers and imaging protocols, artificial intelligence applied to Canadian imaging and records to shorten time to diagnosis, non-hormonal drug targets aimed at inflammation and pain, and trials comparing surgical and medical management pathways.

Clinical studies are how those questions get answered. Taking part is voluntary, you give informed consent before anything begins, and you can stop at any time without affecting the care you get from your own doctor. Joining a study does not mean giving up your current treatment, and no one can tell in advance whether a study will help you personally.

Learn more from Canadian sources

• The Endometriosis Network Canada
• EndoAct Canada
• Health Canada: endometriosis and sexual and reproductive health services
• Your Period, Society of Obstetricians and Gynaecologists of Canada