Intended for healthcare professionals

Clinical Review Extracts from “Clinical Evidence”


BMJ 2000; 320 doi: (Published 27 May 2000) Cite this as: BMJ 2000;320:1449
  1. Cynthia M Farquhar, associate professor (c.farquhar{at}
  1. Department of Obstetrics and Gynaecology, National Women's Hospital, Private Bag 92 189, Auckland 3, New Zealand


    Definition: Endometriosis is characterised by ectopic endometrial tissue, which can cause dysmenorrhoea, dyspareunia, non-cyclical pelvic pain, and subfertility. Diagnosis is made by laparoscopy. Most endometrial deposits are found in the pelvis (ovaries, peritoneum, uterosacral ligaments, pouch of Douglas, and rectovaginal septum). Extrapelvic deposits, including those in the umbilicus and diaphragm, are rare. Endometriomas are cysts of endometriosis within the ovary.


    Interventions In women with pain attributed to endometriosis


    Beneficial: Hormonal treatments (danazol, medroxyprogesterone, gestrinone, gonadotrophin releasing hormone analogues)

    Combined ablation of endometrial deposits and uterine nerve

    Postoperative hormonal treatment

    Cystectomy for ovarian endometrioma (better than drainage)

    Likely to be beneficial:

    Likely to be beneficial: Oral contraceptive pill

    Unknown effectiveness:

    Unknown effectiveness: Dydrogesterone

    Laparoscopic uterine nerve ablation (LUNA)

    Laparoscopic ablation of endometrial deposits

    Preoperative hormonal treatment

    In women with subfertility attributed to endometriosis


    Beneficial: Laparoscopic ablation or excision of endometrial deposits

    Cystectomy for ovarian endometrioma (better than drainage)

    Unlikely to be beneficial:

    Unlikely to be beneficial: Hormonal treatment

    Postoperative hormonal treatment

    Incidence/prevalence: In asymptomatic women, the prevalence ranges from 2% to 22%, depending on the diagnostic criteria used and the populations studied.14 In women with dysmenorrhoea, the incidence of endometriosis ranges from 40% to 60%, and in women with subfertility it ranges from 20% to 30%.2 5 6 The severity of symptoms and the probability of diagnosis increase with age.7 Incidence peaks at about age 40.8 Symptoms and laparoscopic appearance do not always correlate.9

    Aetiology: The cause is unknown. Risk factors include early menarche and late menopause. Embryonic cells may give rise to deposits in the umbilicus, while retrograde menstruation may deposit endometrial cells in the diaphragm.10 11 Oral contraceptives reduce the risk of endometriosis, and this protective effect persists for up to a year after their discontinuation.9

    Prognosis: We found one small randomised controlled trial (RCT) in which repeat laparoscopy was performed in the women treated with placebo. Over 12 months, endometrial deposits resolved spontaneously in a quarter, deteriorated in nearly half, and were unchanged in the remainder.12

    Aims: To relieve pain (dysmenorrhoea, dyspareunia, and other pelvic pain) and to improve fertility, with minimal adverse effects.

    Outcomes: American Fertility Society scores for size and number of deposits; recurrence rates; time between stopping treatment and recurrence; rate of adverse effects of treatment. In women with pain: relief of pain, assessed by visual analogue scale and subjective improvement. In women with subfertility: cumulative pregnancy rate, live birth rate. In women undergoing surgery: ease of surgical intervention (rated as easy, average, difficult, or very difficult).13


    • Competing interests CF was reimbursed in 1995 by ICI, the manufacturer of Zoladex, for helping to develop educational programmes.

    • Embedded Image

    • This review is one of 87 chapters from the second issue of Clinical Evidence

      Clinical Evidence is published by BMJ Publishing Group and American College of Physicians-American Society of Internal Medicine. The second issue is available now, and Clinical Evidence will be updated and expanded every six months. Individual subscription rate, issues 3 and 4, £75/$140; institution rate £160/$245. For more information including how to subscribe, please visit the Clinical Evidence website at

      View Full Text

      Log in

      Log in through your institution


      * For online subscription