Journal of the European Society for Gynaecological Endoscopy


Endometriosis classification systems: an international survey to map current knowledge and uptake †,‡

International Working Group of AAGL, ESGE, ESHRE and WES, K.T. Zondervan 1,2, S. Missmer 3,4,5, M.S. Abrao 6,7, J.I. Einarsson 8, A.W. Horne 9, N.P. Johnson 10, T.T.M. Lee 11, J. Petrozza 12, C. Tomassetti 13,14, N. Vermeulen 15, G. Grimbizis 16, R. L. De Wilde *17.

1 Nuffield Department of Women’s & Reproductive Health, University of Oxford, Oxford Endometriosis CaRe Centre, Oxford, Oxfordshire, UK
2 University of Oxford, Wellcome Centre for Human Genetics, Oxford, Oxfordshire, UK
3 Department of Obstetrics, Gynecology and Reproductive Biology, Michigan State University College of Human Medicine, East Lansing, MI, USA
4 Department of Epidemiology, Harvard University T H Chan School of Public Health, Boston, MA, USA
5 World Endometriosis Research Foundation, WERF, London, UK
6 Disciplina de Ginecologia, Departamento
de Obstetricia e Ginecologia, Faculdade de Medicina FMUSP, Universidade de Sao Paulo, Sao Paulo, SP, Brazil;
7 Gynecologic Division, BP-A Beneficencia Portuguesa de Sao Paulo, Sao Paulo, SP, Brazil
8 Division of Minimally Invasive Gynecologic Surgery, Department of Obstetrics and Gynecology, Brigham and Women’s Hospital, Boston, MA, USA
9 University of Edinburgh, MRC Centre for Reproductive Health, QMRI, Edinburgh, UK
10 Robinson Research Institute, University of Adelaide, Adelaide, SA, Australia
11 Department of Obstetrics, Gynecology and Reproductive Sciences, Magee Womens Hospital of UPMC, Pittsburgh, PA, USA
12 Department of Obstetrics and Gynecology, Massachusetts General Hospital Fertility Center, Boston, MA, USA
13 University Hospitals Leuven, Dept. Obstetrics and Gynaecology, Leuven University Fertility Center, Belgium
14 KU Leuven, Faculty of Medicine, Dept. Development and Regeneration, LEERM (Lab of Endometrium, Endometriosis and Reproductive Medicine), Belgium
15 ESHRE, Central Office, Strombeek-Bever, Belgium
16 1st Dept Obstet Gynecol, Medical School, Aristotle University of Thessaloniki, Thessaloniki, Greece
17 Carl von Ossietzky Universitat Oldenburg, University Hospital for Gynecology, Oldenburg


Endometriosis, infertility, classification, staging, reporting, survey, revised American Society for Reproductive Medicine, endometriosis fertility index, ENZIAN

Published online: Apr 03 2022


Background: In the field of endometriosis, several classification, staging and reporting systems have been developed and published, but there are no data on the uptake of these systems in clinical practice.

Objectives: The objective of the current study was to examine whether clinicians routinely use the existing endometriosis classification systems, which system do they use and what are the clinicians’ motivations?

Materials and Methods: A cross-sectional study was performed to gather data on the current use of endometriosis classification systems, problems encountered and interest in a new simple surgical descriptive system for endometriosis. Of particular focus were three systems most commonly used: the Revised American Society for Reproductive Medicine (rASRM) classification, the Endometriosis Fertility Index (EFI), and the ENZIAN classification. Data were analysed by SPSS. A survey was designed using the online SurveyMonkey tool consisting of 11 questions concerning three domains—participants’ background, existing classification systems and intentions with regards to a new classification system for endometriosis. Replies were collected between 15 May and 1 July 2020.

Main outcome measures: Uptake, feedback and future intentions.

Results: The final dataset included the replies of 1178 clinicians, including surgeons, gynaecologists, reproductive endocrinologists, fertility specialists and sonographers, all managing women with endometriosis in their clinical practice. Overall, 75.5% of the professionals indicate that they currently use a classification system for endometriosis. The rASRM classification system was the best known and used system, the EFI system and ENZIAN system were known by a majority of the professionals but used by only a minority. The lack of clinical relevance was most often selected as a problem with using any system. The findings of the survey suggest that clinicians worldwide are open to using a new classification system for endometriosis that can achieve standardised reporting, and is clinically relevant and simple.

Conclusions: Even with a high uptake of the existing endometriosis classification systems (rASRM, ENZIAN and EFI), most clinicians managing endometriosis would like a new simple surgical descriptive system for endometriosis.

What is new? The findings therefore support future initiatives for the development of a new descriptive system for endometriosis and provide information on user expectations and conditions for universal uptake of such a system.