Modelling a risk classification of aneuploidy in human embryos using non-invasive morphokinetics

TLDR

The study aimed to determine whether morphokinetic differences between aneuploid and euploid embryos could aid in selecting euploid embryos for transfer. The authors collected and blindedly analyzed EmbryoScope time‑lapse images from 98 blastocysts, then compared morphokinetic variables to ploidy determined by trophectoderm biopsy and array CGH or SNP array. Aneuploid embryos exhibited delayed compaction and blastocyst formation relative to euploid embryos, while early cell‑cycle dynamics were similar, suggesting the model could help avoid selecting embryos at high risk of aneuploidy.

Abstract

This study determined whether morphokinetic variables between aneuploid and euploid embryos differ as a potential aid to select euploid embryos for transfer. Following insemination, EmbryoScope time-lapse images from 98 blastocysts were collected and analysed blinded to ploidy. The morphokinetic variables were retrospectively compared with ploidy, which was determined following trophectoderm biopsy and analysis by array comparative genomic hybridization or single-nucleotide polymorphic array. Multiple aneuploid embryos were delayed at the initiation of compaction (tSC; median 85.1 hours post insemination (hpi); P=0.02) and the time to reach full blastocyst stage (tB; median 110.9hpi, P=0.01) compared with euploid embryos (tSC median 79.7 hpi, tB median 105.9 hpi). Embryos having single or multiple aneuploidy (median 103.4 hpi, P=0.004 and 101.9 hpi, P=0.006, respectively) had delayed initiation of blastulation compared with euploid embryos (median 95.1hpi). No significant differences were observed in first or second cell-cycle length, synchrony of the second or third cell cycles, duration of blastulation, multinucleation at the 2-cell stage and irregular division patterns between euploid and aneuploid embryos. This non-invasive model for ploidy classification may be used to avoid selecting embryos with high risk of aneuploidy while selecting those with reduced risk.