I know exactly how you feel. I was in a similar situation with my first cycle. I did toss up whether or not to transfer the 2 embies we had, but neither of us wanted twins and I felt better knowing I'd have a back up. I transferred the first fresh 1 and it was a bfn. I was sooooo disappointed and thought that maybe if I had transferred the 2 I'd be pregnant. But then, after more thinking I realised that maybe it was my body and not necessarily the embryo, everything needs to be perfect. So we went on to our FET and my embie didn't survive the thaw, this obviously made me even more upset. But, to be honest, looking back now, I really don't think that it would have if I transferred the 2 at the beginning because I was so stressed that cycle and very anxiou, and I did feel VERY relaxed on the FET cycle and felt confident that if the embie thawed I'd have a good shot because I was in a better mind set and not so anxious. I guess to answer your question, because your embies are already frozen, it really makes no difference transferreing 1 or 2, either way they still have to survive the thaw. I would probably do 1 at a time so that if things aren't perfect in the first cycle the doc can correct it in the next one. Good luck