Hello,
Pop on and join the IUI chatter and meet all the girls, between us we can just about answer anything. Please try and stay positive it can work. I have had three cycles, 2 of which have been successful, sadly one ended in miscarriage but I am currently 5 wks pg tomorrow on cycle no 3 so I am keeping everything crossed that this is a sticky one.
On the off chance that it doesn't work first time, don't be disheartened, many get their BFP on 2nd/3rd cycle and often treat the first one as a trial and error cycle to see how your body responds.
You probably have a better chance with being unexplained and everything should then work in your favour if there is nothing actually stopping you from getting pg.
Wishing you the best of luck!
jxx