The endometrium is a tissue that lines the inside of the uterus and is shed during each menstrual cycle. Endometriosis is a gynecological condition characterized by growth of endometrial-like tissue outside of the uterus and is associated with immune dysfunction as well as inflammation. Its growth is stimulated by estrogenic female hormones. The tissue can be found in or around the intestines, rectum, ovaries, fallopian tubes, the bladder, pelvic cavity, etc. Women will present with symptoms such as dysmenorrhea (painful periods), dyspareunia (pain with intercourse), GI symptoms, pelvic pain and infertility.

A study found that migraine was 1.7 times more common in women with endometriosis than in those without the disease and a majority of the women experienced migraine after their endometriosis diagnosis rather than before their diagnosis (78.8% vs. 21.2%).1