Metformin

Hi everyone I am 33 years old. I am trying for baby #3. I had a m/c in February 2015 it toke me 8 months to get pregnant. I have not stop trying at all. I have been on 5-6 cycles of clomid and that did not work but my husband was going thru a rough time. I am 204lbs and my doctor put me on Metformin 500mg 2 times a day. Has anyone had luck with metformin or should I take it with clomid 50mg?