IUI/trigger shot

My husband and I have been ttc for almost three years with no luck. We recently started doing ultrasounds to monitor my cysts to do IUI. Today I found out my cysts are where they need to be (size) and we are doing IUI Monday but my doctor decided against the trigger shot because of cost and he thinks I will be fine without it. Has anyone had success without the shot?! This is my second round of clomid so I'm hoping that will be enough!