Does early cleavage correlate with chromosome constitution in human preimplantation embryos?

Abstract

IntroductionThe purpose of this study is to analyze the correlation between the occurrence of early cleavage and chromosome constitution of embryos from preimplantation genetic screening (PGS) and preimplantation genetic diagnosis (PGD). Material and methodsA total of 595 embryos from 96 cycles were included in this retrospective study. ResultsWhen clinical pregnancy rates per transfer were compared, statistically significant differences were observed between patients that had at least one early cleavage (ECpos) embryo and patients no EC (ECneg) (35.7% vs. 6.7%; p<.001). Statistically significant differences were found between EC, No PN and 2PN embryos at 26h, good embryo quality at day 2 (71.4%, 55.6% and 40.7%, respectively; p<.05) and in blastocyst rate (43.3% EC vs. no early cleavage embryos (NEC) 27.1%; p<.001) in PGS cycles. These differences were not found in the PGD group. Early-cleaved embryos exhibited less chromosome abnormalities than No PN and 2PN group in PGS (61%, 69.4% and 77.2%; p<.05) and differences in PGD group (69.8%, 76.2% and 66.7%; p<.05). DiscussionEarly cleavage has shown to correlate with embryo quality, with the capacity to develop up to blastocyst stage, as well as with euploid chromosome constitution.