Yes, since blastocysts (day 5-6 after fertilization) are more likely to attach to the uterine lining, as they are synchronized with the uterine lining and allows for a more accurate selection process. Thus, if we transfer two class A blastocysts, they will have higher chances of implanting than two class A embryos on day 3.
Does the day of embryo transfer influence how many embryos to transfer?
By Rebeca Reus BSc, MSc (embryologist).
Last Update: 09/13/2018
Degree in Human Biology (Biochemistry) from the Pompeu Fabra University (UPF). Official Master's Degree in Clinical Analysis Laboratory from the UPF and Master’s Degree about the Theoretical Basis and Laboratory Procedures in Assisted Reproduction from the University of Valencia (UV).