Fourth round of clomid at higher dose

So I just finished taking my fourth round of clomid. The first three were at 50mg and this one is at 100mg. All rounds have been taken cd 5-9 and I've ovulated consistently on cd 15 every time as well. So frustrating not to be pregnant still. Seeing a new fertility md Tuesday to set up iui next month of this round of clomid doesn't end in a pregnancy. Have any of you had luck with iui? Or any advice while I wait? :) I'm almost just wanting to do Ivf because I've heard so many people say iui didn't work for them and they wish they would have just done Ivf