With today's technology it is possible to thaw blastocysts, biopsy, then refreeze awaiting the results.
So there are two alternatives if one is banking; one is to biopsy before freezing the second is to collect embryos in several cycles, then biopsy the fresh of the last cycle with the frozens from the previous cycles. Which one does depends on the policy of the IVF center and the genetics lab and is mostly an economic decision.
Talk to your doctor about their policy and what would be best for you. Certainly you can consider thawing and testing the ones already frozen.
Arthur L. Wisot, M. D.
Reproductive Partners Medical Group
Redondo Beach, California