The simplified SART embryo scoring system is highly correlated to implantation and live birth in single blastocyst transfers.

OBJECTIVE: Prior studies have validated the ability of the SART embryo scoring system to correlate with outcomes in cleavage stage embryo transfers. However, this scoring system has not been evaluated in blastocyst transfers. The objective of this study was to estimate the correlation between the simplified SART embryo scoring system and ART cycle outcomes in single blastocyst transfers.

MATERIALS AND METHODS: All fresh, autologous single blastocyst transfers cycles from a large ART center from 2010 were analyzed. Blastocysts were given a single grade of good, fair, or poor based upon SART criteria which combines the grading of the inner cell mass and trophectoderm. Multiple logistic regression assessed the predictive value of the SART grade on embryo implantation and live birth.

RESULTS: Seven hundred seventeen fresh, autologous single blastocyst transfers cycles were included in the analysis. The live birth rate was 52 % and included both elective and non-elective SBT. Chi square analysis showed higher live birth in good grade embryos as compared to fair (p=0.03) and poor (p=0.02). Univariate binary logistic regression analysis demonstrated SART embryo grading to be significantly correlated with both implantation and live birth (p<0.01). This significance persisted when patient age, BMI, and the stage of the blastocyst were controlled for with multiple logistic regression. In five patients with a poor blastocyst score, there were no live births.

CONCLUSION: These data demonstrate that the SART embryo scoring system is highly correlated to implantation and live birth in single blastocyst transfers. Patients with a good grade embryo are excellent candidates for a single blastocyst transfer.