Are cleavage anomalies, multinucleation, or specific cell cycle kinetics observed with time-lapse imaging predictive of embryo developmental capacity or ploidy? - Fertility and Sterility

To determine whether cleavage anomalies, multinucleation, and specific cellular kinetic parameters available from time-lapse imaging are predictive of developmental capacity or blastocyst chromosomal status. Retrospective analysis of prospectively collected data. Single academic center. A total of 1,478 zygotes from patients with blastocysts biopsied for preimplantation genetic screening were cultured in the EmbryoScope. Trophectoderm biopsy. Embryo dysmorphisms, developmental kinetics, and euploidy. Of the 767 biopsied blastocysts, 41.6% (95% confidence interval [CI], 38%–45%) were diagnosed as euploid. Individual dysmorphisms such as multinucleation, reverse cleavage, irregular chaotic division, or direct uneven cleavage were not associated with aneuploidy. Direct uneven cleavage and irregular chaotic division embryos did, however, exhibit lower developmental potential. The presence of two or more dysmorphisms was associated with an overall lower euploidy rate, 27.6% (95% CI 19%–39%). Early embryo kinetics were predictive of blastocyst development but not ploidy status. In contrast, chromosomal status correlated significantly with start time of blastulation (tSB), expansion (tEB), and the tEB-tSB interval. A lower euploidy rate, 36.6% (95% CI 33%–42%) was observed with tSB ≥ 96.2 hours, compared with 48.2% with tSB < 96.2 (95% CI 42%–54%). A drop in euploidy rate to 30% (95% CI 25%–37%) was observed in blastocysts with delayed expansion (tEB > 116). The proportion of euploid blastocysts was increased with tEB-tSB intervals of ≤13 hours. A logistic regression model to enhance the probability of selecting a euploid blastocyst was constructed. Morphokinetics may aid in selection of euploid embryos from a cohort of day 5/6 blastocysts. Discuss: You can discuss this article with its authors and other readers at https://www.fertstertdialog.com/users/16110-fertility-and-sterility/posts/28800-24784 Recognition of the health risks and financial costs associated with multiple pregnancies has been a driving force for IVF laboratories to move toward elective single ET (eSET). The adoption of an eSET policy demands not only optimization of culture technology but also embryo selection/deselection techniques that enhance the possibility of the selection of embryos with the greatest implantation potential. Embryonic aneuploidy contributes significantly to failed implantation. An interesting study by Yang et al. reported a euploidy rate of only 44% in good-prognosis patients undergoing IVF (1x1Yang, Z., Liu, J., Collins, G.S., Salem, S.A., Liu, X., Lyle, S.S. et al.