A Review of The Society for Assisted Reproductive
Technology Embryo Grading System and Proposed
The Society for Assisted Reproductive Technology (SART) method of embryo grad- ing is unique, simple, and widely practiced, and its use has been mandatory for SART membership programs since 2010. Developed by SART in 2006, the current embryo grading system categories, “good, fair, and poor,” are limited because they do not describe the best 1-2 embryos in the interest of keeping pace with the shift in clinical practice to be more selective and to transfer fewer embryos. This inspired us to conduct a review on the SART embryo grading system.
In this retrospective study, the literature on evaluation of human embryo quality in gen-
eral, and the SART method of evaluation in particular, were reviewed for the period of
2000 to 2014. A multifaceted search pertaining to methods of embryo grading and trans-
fer using a combination of relevant terms [embryo, mammalian, embryo transfer, grade,
grading, morphology, biomarkers, SART, and
Very few studies have evaluated the efficacy of the SART embryo grading method. The present study suggests the necessity for revision of the current SART grading system. The system, as it is now, lacks criteria for describing the cohort specific best embryo and thus is of limited use in single embryo transfer. The study foresees heightened descriptive efficiency of the SART system by implementing the proposed changes.
Strengths and weaknesses of the SART embryo grading were identified. Ideas for selecting the best cohort-specific embryo have been discussed, which may trigger methodological improvement in SART and other embryo grading systems.