Media, Morphokinetics, and Mosaicism

Embryonic aneuploidy is the underlying etiology for the majority of failed implantation and miscarriage. Preimplantation genetic screening (PGS) with transfer of a euploid embryo has been advocated as a strategy for increasing live birth rates with a single embryo transfer. Culturing embryos to the blastocyst stage for trophectoderm biopsy is a requirement for PGS. Several commercially-available single-step embryonic culture media with varying composition have been established for use in the IVF laboratory. Early reports have suggested differences in clinical outcomes, such as aneuploidy and miscarriage rates, with distinct culture media currently in standard use.1,2 However, there have been no clinical trials demonstrating the superiority of any one commercially-available culture media formulation. As a result, clinics use media with varying composition based upon familiarity and cost.