Prospective Randomized Study to Evaluate the Effect of Embryonic Observation on the Gestation (PROdE)

In a conventional in vitro fertilization (IVF) cycle, daily microscopic observation of embryos outside the incubator to assess their morphology and establish a selection process is performed. In this way it is possible to know which embryo or embryos have greater implantantion capacity and will be transferred to the uterus to obtain a viable pregnancy. However, these observations can produce deleterious effects on embryo development due to changes in temperature, pH and osmolarity of the culture media, as well as a negative effect of direct light microscope for observation. This project aims to test the hypothesis that non-embryonic observation produces a beneficial effect on embryo quality until day 5 of development (blastocyst stage) and, therefore, on rates of implantation and ongoing gestation, compared with the conventional protocol of observations under the inverted microscope on days two, three and five of development.