Blastocyst morphology after warming and clinical outcomes. Graph depicts relationship between embryo morphology and clinical outcomes in blastocyst (BL) vitrification-warming cycles. Embryos were graded as expanded blastocysts (EBL), early blastocysts, morula (Mor) or non re-expanded blastocysts (NR). Transfers were divided in to four general groups based on carrier used for vitrification and the morphology of the transferred embryos: 1-EBL only, 2-EBL/ Early BL (transfers with mixed stages), 3-Early BL only and 4-Mor/NR. Relationship between embryo morphology at transfer and resultant CPR and IR was examined. The number of transfers for each group and respective carrier is shown on the graph. Bars depict percent of transfers resulting in clinical pregnancy (CPR) and percent of embryos implanting (IR). * P < 0.05 CPR and IR for Rapid-i Group 1 vs. Groups 3 and 4 ** P < 0.05 CPR and IR for Cryoloop Group 1 vs. Group 4.