The correlation between morphology and implantation of euploid human blastocysts

Abstract Research question Does the composite morphology score or a particular developmental component (expansion stage, inner cell mass [ICM] or trophectoderm [TE]) of euploid blastocysts undergoing single frozen embryo transfer (FET) impact ongoing pregnancy/live birth (OP/LB) rates? Design Retrospective cohort study including a total of 2236 embryos from 1629 patients who underwent single euploid FET between 2012 and 2017. Results Embryos with an ICM grade of A compared with C had a higher OP/LB rate (55.6% versus 32.3%, P Conclusions Among euploid embryos, ICM morphology is the best predictor of sustained implantation; however, a composite score may provide additional guidance. While there is a known benefit in genomic screening prior to embryo selection, morphology provides individualized, prognostic information about implantation potential.