and use Endometrin (vag tablets) or like you mentioned, Crinone gel. PIO is not a requirement of IVF.
I'm sure that Jaime and gone-fshn did not use PIO in their BFP cycles. Jaime k=just gave birth last month and gone_fshn is due any day now. You can find them on the PG board, where you can also ask about any others who've had success.