Trying to conceive at 35

I've been trying to conceive for 2 yrs.  I've been to the fertility specialist and had my tubes checked, etc.  My husband has had a semen analysis.  We did an IUI without any success. ?My husband doesn't have any children.  I have a 10yr. old.  I've tried Vitex, fertility blend, now I'm using gonal f that I had left over from when I did the IUI.  I'm so frustrated with not conceiving.  ???