An Evidence-Based Scoring System for Prioritizing Mosaic Aneuploid Embryos Following Preimplantation Genetic Screening

摘要

Human blastocyst embryos after preimplantation genetic screening (PGS) are comprised of mostly euploid embryos and some mosaic embryos. When there are no euploid cells following PGS, only mosaic embryos are available for transfer. Recent studies have shown that transfer of some mosaic embryos may result in the birth of healthy children. It is unclear whether all mosaic embryos should be considered for transfer, and if so, which types should be transferred that can result in live healthy babies. Very few prospective follow-up studies have been performed examining outcome of pregnancies achieved following transfer of mosaic aneuploid embryos. In the absence of such data, it is possible to extrapolate from cytogenetic analyses of chorionic villus samples performed for prenatal diagnosis to assess whether the mosaic state involves the fetus itself or is only confined to the placenta.