Existing evidence shows that culturing embryos till stage 5-6 of development, we can increase the pregnancy success rates per fresh and frozen embryo transfer. This is due to the fact that the embryos to transfer or cryopreserve can be selected more properly, since blastocysts have a higher implantation potential. It also improves embryo-endometrial synchrony.
One should keep in mind that about 50 percent of viable embryos will arrest on day 3 of development. In other words, they will not make it to blastocyst stage.
Read the full article on: Day 5 vs. Day 3 Embryo Transfer – What Are the Pros & Cons? ( 69).
Read the full article on: Embryo transfer: when and how is it done? ( 86).

Patricia Recuerda Tomás
B.Sc., M.Sc.
Bachelor's Degree in Biology from the University of Alcalá de Henares. Master’s Degree about the Theoretical Basis and Laboratory Procedures in Assisted Reproduction from the University of Valencia (UV). Extensive experience working at several Assisted Reproduction laboratories.
License: 19882M