justjuice Im so sorry that you havent been one of the very lucky ones with the IVF cycles It is sooo frustrating being told you have 'unexplained' infertility I havent done IUI after IVF but wanted to tell you we tried IUI then IVF with a total of 11 cycles, no baby, then our naturally conceived bubba came along. So I think your 'theory' may have a bit of possibility behind it, we couldnt get those perfect blastocysts to stick IMO if thats the path you want to try then why not give it a go, especially if you dont try it, will you always wonder 'what if'.