The obstetrical and infant outcomes of trophectoderm biopsy on preimplantation genetic testing embryos after frozen single embryo transfer cycles.

Purpose: To investigate if trophectoderm (TE) biopsy on preimplantation genetic testing (PGT) increases the risk of obstetrical and infant outcomes after frozen single blastocyst transfer cycles.

Methods: This retrospective cohort study included all frozen single blastocyst transfer cycles conducted between January 2012 and December 2017 at Peking University Third Hospital. A total of 1492 patients in the PGT group and 600 patients in the non-PGT group were analyzed. The primary outcomes were clinical pregnancy rate, live birth rate, and early motor development milestones. Secondary outcomes included miscarriage, obstetric complications, and infant outcomes.

Results: The PGT group had younger parental ages and higher antral follicle counts, whereas the non-PGT group had lower sperm quality. The clinical pregnancy rate (52.7 vs. 45.2%, p = 0.002) and live birth rate (44.0 vs. 32.8%, p < 0.001) were significantly higher in the PGT group, while the miscarriage rate (13.6 vs. 22.5%, p < 0.001) was lower. In terms of early motor development, infants in the PGT group achieved milestones such as independent sitting, hand and knee crawling, and standing earlier (p < 0.001), although the timing of independent walking did not significantly differ between groups (p = 0.304). No significant differences were found between the two groups regarding pregnancy complications, infant outcomes, or early motor development. These findings were further confirmed through adjusted analyses.

Conclusion: PGT was associated with higher live birth rate and lower miscarriage rate in first single blastocyst transfer cycles. Blastocyst biopsy may not increase the risk of pregnancy complications or negatively impact early motor development in infants.