Background
Preimplantation genetic testing for chromosomal structural rearrangements (PGT-SR) has been widely utilized to select euploid embryos in patients carrying balanced chromosomal rearrangements (BCRs) by chromosome copy number analysis. However, reliable and extensively validated PGT-SR
Methods
In this prospective, multicenter, cohort study, carriers with BCRs undergoing PGT-SR were recruited across 12 academic fertility centers within China. PGT-SR was performed using genome-wide SNP genotyping and haplotyping approach. Parental haplotypes were phased by available genotypes from a close relative or an unbalanced embryo. The karyotypes of embryos were inferred from the haplotypes. Only a single embryo was transferred in each cycle. Findings: Between April 2018 and March 2023, 1298 carriers we randomly enrolled. A total of 7867 blastocysts from 1603 PGT-SR cycles were biopsied, in which 7750 (98.51%) were successfully genotyped and analyzed. Overall, 75.98% (1218/1603) of cycles obtained euploid embryos and 53.15% (852/1603) generated non-carrier embryos. The proportion of carrier and non-carrier embryos was similar in different subgroups. A total of 1030 non-carrier and 439 carrier embryos were transferred, 817 healthy babies were delivered cumulatively. Our