Letrozle vs Injectables with IUI

Hi ladies,

Our first IUI was done with 10mg letrozle cd 3-7 with the trigger shot. It was unsuccessful but I did have 3 mature follicles.

I did letrozle again cd 3-7 and it did not produce mature follicles, so no IUI this month. We're desperately wanting a baby and have been TCC for almost 2 years.

Can anybody tell me your experiences with injectables & IUI? RE mentioned trying another round of Letrozle then Injectables but I don't want it to fail and may want to go right to Injectables or heck straight to IVF. Any help is appreciated! Feeling defeated 😔