World endometriosis society consensus on the classification of endometriosis

Neil P. Johnson, Lone Hummelshoj, G. David Adamson, Jörg Keckstein, Hugh S Taylor, Mauricio S. Abrao, Deborah Bush, Ludwig Kiesel, Rulla Tamimi, Kathy L. Sharpe-Timms, Luk Rombauts, Linda C. Giudice

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STUDY QUESTION: What is the global consensus on the classification of endometriosis that considers the views of women with endometriosis? SUMMARY ANSWER: We have produced an international consensus statement on the classification of endometriosis through systematic appraisal of evidence and a consensus process that included representatives of national and international, medical and non-medical societies, patient organizations, and companies with an interest in endometriosis. WHAT IS KNOWN ALREADY: Classification systems of endometriosis, developed by several professional organizations, traditionally have been based on lesion appearance, pelvic adhesions, and anatomic location of disease. One system predicts fertility outcome and none predicts pelvic pain, response to medications, disease recurrence, risks for associated disorders, quality of life measures, and other endpoints important to women and health care providers for guiding appropriate therapeutic options and prognosis. STUDY DESIGN, SIZE, DURATION: A consensus meeting, in conjunction with pre- and post-meeting processes, was undertaken. PARTICIPANTS/MATERIALS, SETTING, METHODS: A consensus meeting was held on 30 April 2014 in conjunction with the World Endometriosis Society's 12th World Congress on Endometriosis. Rigorous pre- and post-meeting processes, involving 55 representatives of 29 national and international, medical and non-medical organizations from a range of disciplines, led to this consensus statement. MAIN RESULTS AND THE ROLE OF CHANCE: A total of 28 consensus statements were made. Of all, 10 statements had unanimous consensus, however none of the statements was made without expression of a caveat about the strength of the statement or the statement itself. Two statements did not achieve majority consensus. The statements covered women's priorities, aspects of classification, impact of low resources, as well as all the major classification systems for endometriosis. Until better classification systems are developed, we propose a classification toolbox (that includes the revised American Society for Reproductive Medicine and, where appropriate, the Enzian and Endometriosis Fertility Index staging systems), that may be used by all surgeons in each case of surgery undertaken for women with endometriosis. We also propose wider use of the World Endometriosis Research Foundation Endometriosis Phenome and Biobanking Harmonisation Project surgical and clinical data collection tools for research to improve classification of endometriosis in the future, of particular relevance when surgery is not undertaken. LIMITATIONS, REASONS FOR CAUTION: This consensus process differed from that of formal guideline development, although based on the same available evidence. A different group of international experts from those participating in this process may have yielded subtly different consensus statements. WIDER IMPLICATIONS OF THE FINDINGS: This is the first time that a large, global, consortium-representing 29 major stake-holding organizations, from 19 countries - has convened to systematically evaluate the best available evidence on the classification of endometriosis and reach consensus. In addition to 21 international medical organizations and companies, representatives from eight national endometriosis organizations were involved, including lay support groups, thus generating and including input from women who suffer from endometriosis in an endeavour to keep uppermost the goal of optimizing quality of life for women with endometriosis.

Original languageEnglish
Pages (from-to)315-324
Number of pages10
JournalHuman Reproduction
Issue number2
Publication statusPublished - 2017


  • Classification
  • Consensus
  • EFI
  • Endometriosis
  • Enzian
  • Evidence based
  • R-ASRM
  • Staging
  • WERF EPHect
  • World endometriosis society Sao Paulo consortium

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