I'm told the drop off from day 3 to blast is normal. First cycle we went from 12 to 4, second cycle we went from 18 to 7 - all in that day 3 to blast step. My FS is big on blast culture - in his words Not all embryos are capable of becoming a baby, growing them to blastocyst is the first step towards filtering out the bad ones. If they don't make it to blast, they were never going to get you pregnant. That said, he still does some day 2/3 transfers in women who don't get many embryos at all.

He also says that freezing them and thawing them is another step in filtering out the bad ones. He told me that all embryos that failed to thaw turned out to be defective when they checked them. I haven't found a reference for this study, but I'd like to think my FS is telling me the truth!

Good luck with everything, Nat. We may have had 7 blasts, but they turned out to be fairly crappy blasts! I'm pretty much at the point where I'm going to see this cycle as a success if I can just get to have a fresh transfer - regardless of what may happen after that.

BW