Endometriosis occurs when tissue like the lining of the uterus (the endometrium) grows and implants outside of the uterus on other parts of the body. This tissue responds to the menstrual cycle the same way that the tissue lining the uterus does; each month, the tissue will build up, break down, and shed. However, unlike menstrual blood, which flows out of the uterus through the vagina, the blood and tissue from endometriosis has no way of leaving the body. Endometriosis is most often found on the ovaries, fallopian tubes, bowel, rectum, bladder, or on other pelvic organs or surfaces in the abdominal area. That said, endometriosis has been found on every organ in the body, except for the spleen. This can cause internal scarring, painful periods, chronic pelvic pain, formation of adhesions (bands of scar tissue that connect organs), infertility, and other symptoms.

Endometriosis is common, impacting approximately 10% of women and an unknown number of transgender, non-binary, and gender-diverse individuals. Since endometriosis can only be reliably diagnosed through surgery or specific medical imaging, it can take years to diagnose. For some people, endometriosis can be a debilitating condition that can cause chronic pelvic and back pain, severe menstrual cramps, heavy or irregular periods, painful bowel movements, nausea and vomiting, fatigue, and bloating. Other people may never know that they have endometriosis and may never show symptoms. Like other health conditions, there are racial disparities associated with endometriosis due to differential exposures to suspected causes, lack of adequate access to health care, including highly skilled gynaecologic surgeons and bias and discrimination within the health care system. Indigenous, African, Caribbean and Black and other minority populations – and their health care providers – need culturally- and structurally-competent information, resources and care.

Even though endometriosis is common, it is a complex disease that can be challenging to diagnose and treat. Endometriosis can begin in adolescence, but often goes undetected or is inadequately treated for a long period of time. In teens, endometriosis is a common cause of chronic pelvic pain. Symptoms of endometriosis may be similar to other conditions, and because people often experience symptoms differently, it can be challenging to diagnose and treat endometriosis. If you suspect you have endometriosis, it is important you speak to your doctor to discuss care options.