We recently found out that we had 6 euploid embryos and 4 of the 6 were from eggs that fertilized later than the rest. I have seen some people mention that they may have had one or two eggs that fertilized late but haven't seen much about transferring these types of eggs that become embryos and are determined to be normal. They all came back with an AA, AB, or BA grade. Our doctor said to transfer the other two first but that they were viable and was genuinely unsure of how the late fertilization would affect them. To me, it seems like it is more likely that the clinic missed these four when doing the initial fertilization check or did the check too early over all of our 4 late fertilized eggs becoming good quality euploids.