PCOS and miscarriage prevention??

Hi Ladies, Im 33 and ttc#3. I have PCOS but I've had regular cycles for a year every 33 days. I started exercising 3 days weeks and watching carbs which I think got my cycles back on track. Last September I had a MC at 7 weeks baby stopped growing it never had a heart beat. absolutely crushing!!! I had to get a D&C; and it was just a painful and emotional mess! So we decided onve we moved into our new home we would try again. no luck in June, but July i had a chemical pregnancy I tested positive 5 days before AF was due and then negative via blood test 1 day before AF! Again heart breaking IDK what the hell is going on with my body I have a 15 and 7 year old. Ive heard of taking baby asprin, folic acid and B6. so this cycle I took all those in hopes it helps me! AF due 8/19, Im 5 dpo I dont do well with metformin. Any suggestions welcomed?!?