Dr. Marina González of the Ginemed centers answers us. As the doctor tells us:
Although on day 2 of development we can achieve pregnancy by transferring these embryos, it is true that the embryos as they evolve will have a greater probability of success, the optimum being to transfer embryos at the blastocyst stage. Transferring more evolved embryos has several advantages. On the one hand, it is the most physiological, since in a natural pregnancy the embryo reaches the uterus when it is in the blastocyst stage. In addition, the fact of waiting more days until the transfer will allow us to make a natural selection of the embryos that will be lost throughout the cycle. All this means that the probabilities of success by transfer increase when the embryo's evolution is greater.
