Pain and endometriosis

Endometriosis is the commonest cause of chronic pelvic pain in women (Fauconnier and Chapron, 2005). It is characterized by the presence of uterine endometrial tissue outside of the uterus, most commonly in the pelvic cavity. The disorder mainly affects women of reproductive age. Symptoms of endometriosis include recurrent painful periods, painful intercourse, painful defecation during menstruation, chronic lower abdominal pain and hypersensitivity, chronic lower back pain and infertility (Farquhar, 2007). For many women, endometriosis has a negative impact on the ability to work, on family relationships and self-esteem (Huntington and Gilmour, 2005). Many women with endometriosis describe a progression of symptoms over their menstrual life, which may include a mix of different pains and abnormal visceral sensations, indicative of viscero-visceral hyperalgesia and suggestive of neuropathic pain (Horowitz, 2007). Current medical treatments for endometriosis include oral contraceptives, progestogens, androgenic agents, gonadotrophin releasing hormone analogues, as well as laparoscopic surgical excision of the endometriotic lesions. However, management of pain in women with endometriosis is currently insufficient for many women. Here we review the involvement of the nervous system, immune cells and inflammatory response, and hormones in endometriosis as well as current practice in pain management. We suggest that