Michelle Emblenton, biochemist at inviTRA, responds to us in this video:
If we answer this question from purely a technical point of view, it would be that eggs are more fragile than embryos and, in the process of vitrification, it may be that more eggs are lost than would be the case for embryos. As such, from a technical point of view, it is better to freeze embryos than it is to freeze eggs. However, if we are looking at this question from the point of view of the patient and IVF treatments, we need to think about why the woman has chosen to undergo fertility preservation. When you cryopreserve your embryos, you need to keep in mind that your personal situation may change in the future. If a heterosexual couple decides to freeze their embryos for future use, it may unfortunately be the case that that couple later on are no longer together and hence... what happens to those embryos that are belong to both of the couple? In the case of single women who have chosen to preserve embryos using donor sperm, it may be the case in the future they meet a man with whom they wish to have biological children, but this will not be the case as she has frozen her embryos (which have already been fertilized) and not her eggs. In short, embryo cryopreservation may be technically the better technique for women over 35, but it doesn't prevent any future possible problems due to a change in the woman's social situation in the future.
