Thanks Dusty. My OB has indicated that there are no real issues and certainly hasn't mentioned what the cause could possibly be. I'm 31. The only thing he's told me why we are using IUI is that my estrogen levels aren't getting high to ovulate. That's it!! I'm the sort of person who sits back and tends not to ask too many questions as I don't like to be seen as 'High Maintenance'..........i've got an appt with the nurses again on Monday so I'll ask the question.