Factors affecting the reproductive outcome in reciprocal translocation carriers undergoing preimplantation genetic testing for structural rearrangements (PGTSR)

Objective: To investigate the reproductive outcomes of balanced reciprocal translocation carriers and evaluate the association between the number of metaphase-II oocytes retrieved and cumulative live birth rates (LBRs).Methods: This retrospective analysis included 344 preimplantation genetic testing (PGT) for structural rearrangement cycles of 281 couples with balanced reciprocal translocations between January 2018 and January 2021. All patients included in the analysis had either delivered a baby or had used all their embryos after one stimulation cycle. All women were followed up for at least 2 years.Results: After ovarian stimulation and oocyte fertilization, 44.2% of PGT for structural rearrangements cycles achieved a live birth. Carrier's sex and female age did not affect the cumulative LBR of reciprocal translocation carriers. Cumulative LBRs steadily increased with the number of oocytes, reaching 64% when >20 oocytes were retrieved. The cutoff values for achieving at least one live birth were 9.5 metaphase-II (MII) oocytes and 3.5 biopsied embryos.Conclusion: Couples with reciprocal translocations have lower transferable embryo rates and cumulative LBRs. The MII oocytes retrieved may be a crucial factor for cumulative LBRs. A high ovarian response may further increase cumulative LBRs, but avoidance of ovarian hyperstimulation syndrome or other iatrogenic complications should be considered.