#275 : A Comparative Study of Hatching Methods for Biopsy Time and Ploidy Status Assessment

Background and Aims: Preimplantation genetic testing plays a crucial role in assisted reproductive technologies by aiding in the selection of embryos with optimal developmental potential. This study aims to compare the time required for biopsy and evaluate the ploidy status between Day3 and Day4 hatching-based methods and cases without assisted hatching (AH).

Method: We retrospectively analyzed data from 257 embryos from 56 patients between November 2022 and March 2023. Embryos were categorized into three groups: Day3 hatching-based method (n=43), and Day4 hatching-based method (n=134), and cases without AH (n=80). We used Kruskal-Wallis tests and chi-square tests to compare the groups with R software (version 4.1.0) at a significance level of 0.05.

Results: There was a significant difference in the median biopsy time per embryo between the hatching-based methods (H = 6.01, p = 0.049). The Day4 hatching-based method had a significantly shorter biopsy time per embryo than cases without AH (W = 95, p = 0.037). There were no significant differences in the percentages of euploid, aneuploid, or mosaic embryos between the hatching-based methods. The Chi-square test showed no significant differences between the observed and expected percentages of euploid (${\chi }^2$ = 0.22, p = 0.893), aneuploid (${\chi }^2$ = 2.35, p = 0.308), or mosaic (${\chi }^2$= 0.58, p = 0.748) embryos across all hatching-based methods. The Chi-square test of independence showed no significant differences in the percentages of euploid (${\chi }^2$ = 0.56, p = 0.755), aneuploid (${\chi }^2$ = 1.41, p = 0.495), or mosaic (${\chi }^2$ = 0.22, p = 0.896) embryos between the hatching-based methods.

Conclusion: We suggest that the Day4 hatching-based method may provide a significant advantage in terms of shorter biopsy time per embryo compared to cases without AH, but there were no significant differences in the percentages of euploid, aneuploid, or mosaic embryos between the hatching-based methods.