Are you charting? Taking your basal body temp every morning should give you an idea if you're ovulating and what your luteal phase length is. That's where i would start. Once I charted, it became very apparent that I Od late and my LP was short. If everything there looks fine, you may want to have your husband get a sperm analysis done.
I know that might sound like a lot, but I pushed my Dr. to start looking into things knowing something wasn't right based on my tests. We wasted way too much time in the beginning assuming things were okay.
I hope everything is okay for you and you just haven't had great luck so far. I hope you're prego this cycle
We did a bunch of medical assistance the first tiem around and eventually changed to acupuncture and herbs. After 3 months of that I was prego. We skipped the MA this time around and went right to acupuncture. After 3 months we're prego again. We tried naturally this time for 7 months before moving onto acupuncture again. Last time it took us 19 months before we figured out acupuncture might work for us.