What are the advantages of blastocyst culture?
Perhaps the best way to show this is to give an example: If a woman has 15 eggs retrieved, an average of 10 to 12 will fertilise the following day. It is impossible to determine at this point which of these fertilised eggs are most likely to implant and develop into a baby.On the traditional day of embryo transfer (day 3); perhaps 6 of the embryos may be developing into good quality normal embryos. The others may have slowed or stopped their development altogether.
As we are limited by the HFEA to transferring a maximum of 2 embryos, it can be difficult to select the one embryo that may develop into a baby (if any). All 6 embryos may look like they have the same potential. Two additional days development in the blastocyst culture medium allows the natural selection process to continue. Thus, after 5 days of growth in the laboratory, only 2 or 3 of the original embryos may remain viable. We now know the best embryos to transfer.
