PCOS, bipolar, and medications

I have PCOS and bipolar disorder . I take Risperdal for bipolar but it prevents ovulation . I am stopping Topimax for binge eating because it is bad for fetal development. My psychiatrist suggested metformin if I start gaining weight and I have read that can help with ovulation. But what if I’m taking a medication that prevents ovulation? The risperdal really helps stabilize my mood where other drugs do not. And I don’t want to take lithium for fear of negative impact on fetal development in case I can get pregnant. Anyone have any experience with these medications?