Questions about IUI

I have PCOS and me and my SO have been trying to conceive for over 3 years. We have tried clomid first try we got pregnant then miscarried a month and a half later. We just tried femera and doctors said they can uo the does then after that they recommend IUI but I want to know how likely or how much of chance do we have with the IUI and is the IUI procedure painful? We are just beyond ready to be parents. We have heard the "When it happens it happens" and the "It will happen eventually, if God wants you to he will" "Get married first, maybe that's why it's not working"