Last edited 12/2022 and last reviewed 12/2022

This is a common disorder characterized by the presence of endometrial glands and stroma outside of the endometrial cavity (1).

  • it is a benign condition but one which is of great importance in gynaecology because the distressing symptomatology, the association with infertility and the potential for invasion of the gastrointestinal and urinary tracts.
  • these ectopic tissues induce an estrogen-dependent chronic inflammatory process (1) and are usually seen in the pelvis, but lesions in the extraplevic sites have also been reported (e.g. lungs, brain skin, external genitalia) (2)

Classically it is described in women in their thirties and forties, particularly, Caucasians. However, as the use of laparoscopy has become widespread, this description has become less accurate.

  • population prevalence is estimated at 10%, based on prevalence estimates of pelvic pain and infertility in the general population (4)
  • in 2% to 11% of women, endometriosis is an incidental finding during surgery for other indications (4)
  • up to 50% of women presenting with infertility have endometriosis (4)
  • 24-40% of women with chronic pelvic pain have endometriosis (4)

NICE note that (3):

  • delayed diagnosis is a significant problem for women with endometriosis
    • delays of 4 to 10 years can occur between first reporting symptoms and confirming the diagnosis

  • diagnosis can only be made definitively by laparoscopic visualisation of the pelvis, but other, less invasive methods may be useful in assisting diagnosis, including ultrasound

  • management options for endometriosis include pharmacological, non-pharmacological and surgical treatments
    • endometriosis is an oestrogen-dependent condition - most drug treatments for endometriosis work by suppressing ovarian function, and are contraceptive
    • surgical treatment aims to remove or destroy endometriotic lesions
    • choice of treatment depends on the woman's preferences and priorities in terms of pain management and/or fertility

Key points (4):

  • consider endometriosis when women of reproductive age present with abdomino-pelvic pain associated with menstruation, sexual intercourse, urination, defecation, and/or infertility
  • consider gynaecology referral if three months of simple analgesia (with or without combined oral contraceptive pill) is ineffective for suspected endometriosis
  • a normal pelvic exam and/or pelvic ultrasound does not exclude endometriosis