David Adamson's Endometriosis Fertility Index (EFI) is a clinical tool used to predict pregnancy rates after endometriosis surgery. It is the only system that is predictive of fertility, but is not a staging system. The EFI has 6 levels and uses the 1985 American Fertility Society (rAFS) staging system’s total and endometriosis sub-total score separately. The EFI is based 50% on history, 30% on surgical findings at the completion of surgery, and 20% on the rAFS scores.
The 1984 rAFS staging system was renamed the revised American Society of Reproductive Medicine (rASRM) staging system in 1996 after that organization changed their name. The 1996 rASRM endometriosis staging system is the same as the 1984 rAFS endometriosis staging system with additional examples.
The rAFS is the staging system most commonly used at surgery but is not predictive of fertility. It can be used to describe the appearance at surgery and is somewhat predictive of surgical difficulty. The rAFS has 150 points. A score 40 or higher is rAFS stage 4. The rAFS separates stage 4 into scores for 4A (40 to 70 points) and 4B (71 to 150 points). Scores of 71 and higher are generally seen only with severe adhesions. Adhesions, a type of scar tissue, can block the pathway that the eggs use to get to the tube. Canis (1992) also uses the rAFS score of >70 to be stage 5 for endometriosis.
If your physician does not use the EFI, then you can use the following for an approximate score. Note that high scores are good.
(1) Calculate your historical factors score using the sum of the 3 historical factors.
Years of Infertility
(2) Calculate your Surgical Factors score by comparing your understanding of your surgery to the following possibilities. If you have more than one answer, use both your highest and lowest estimates to see how those change the pregnancy rate projection on the Estimated Percent Pregnancy figure below.
(3) Add the totals for your historical factors score and your surgical factors score for a total. Compare the total with the estimated percent pregnancy below. Note that high scores are good.
|EFI Score||Pregnant at 1 Year||Pregnant at 3 Years|
Adamson GD & Pasta DJ. Endometriosis fertility index: the new, validated endometriosis staging system. Fertil Steril 2010;94(5):1609–15
American Fertility Society. Revised American Fertility Society classification of endometriosis 1985. Fertil Steril 43(3):351-352, 1985
American Society for Reproductive Medicine classification of endometriosis: 1996. Fertil Steril 67(5): 817-21, 1997
Updated October 11, 2018