Endometriosis is a well known and common cause of pelvic pain in women. It is a condition where endometrial tissue typically found in the uterus (womb) is found in other parts of the body, commonly on the ovaries, bladder and pelvic floor. It is sometimes found in the lungs, and can occur anywhere in the body. This tissue produces an inflammatory response to hormone changes which manifests as pelvic pain, pain with intercourse and bowel movements, urinary symptoms and infertility. It is estimated that about 10% of women have endometriosis however, some women can have endometriosis but do not have pain.