I never had IUI, this is my first IVF and my insurance will cover it. So I don't really know, sorry...
It wouldn't hurt to try another cycle or two of iui if you are curious about whether it would work, especially if it is covered by insurance. I would think that your re would have the best answer for you on this, though. If you are thinking about it, make sure you say that to the doctor!
I agree with baby1234, maybe you should try fertility clinic...are you taking any medication with it to stimulate your ovaries. I had about 7 IUSs before I moved to IVF.
I take gonal f injections and 10000 units of HCG.. I think though that I didnt ovulate in time I alwasy had the EWCM like 8-10 hours after the IUI