 Preliminary data from the pilot study have shown a higher proportion of euploid embryos for sibling oocytes cultured in vivo vs. in vitro. Moreover, in animal models, in vivo cultured embryos have been described with significant reduction of aneuploidies and with differences in the gene expression levels patterns when compared to in vitro cultured embryos. There is also growing evidence that the culture conditions of human pre-implantation embryos can affect the gene expression regulation with measurable effects on embryos and on newborn children. 