Incidence of the morphological aspect on the rate of implantation of embryos obtained by fertilization in vitro]

1350 embryos obtained by In Vitro Fertilization (IVF) have been examined with the reverse microscope before their transfer in utero. Some embryos are "morphologically normal" (34.7%); some others are atypical. It is difficult to determinate the implantation rate by embryo according to morphological aspect because, most of the time we transfer several embryos to only one patient and we do not know, in case of pregnancy, which one or which ones have developed. Nevertheless, we have tried to appreciate, for 500 embryos transfers after IVF, the incidence of morphological aspect according to the presence or absence of "morphologically normal" embryos. The implantation rate is significantly higher in the groups in which you find "morphological normal" embryos than in the group where they are missing. (19.7% and 19.2% vs 10.2%). It seems that the aspect of the embryo when it is transferred, has an incidence on its future development.