[Oocyte and embryo quality: is their morphology a good criterion?].

This article evaluate the predictive value for implantation and pregnancy rates in IVF of the morphology of oocyte, zygote and embryo. Oocyte morphology does not affect fertilization rate, embryo quality and implantation rate after IVF/ICSI. Multinucleation in normally fertilized embryos is associated with lower implantation and pregnancy rates in in vitro fertilization-embryo transfer cycles. Severe blastomere fragmentation (>25%) is associated with lower delivery rates (1%). Secretion of human leukocyte antigen-G (sHLA-G) by human embryos is associated with a higher in vitro fertilization pregnancy rate.