Hello,
I currently take metformin and did until i was 11 weeks preg with DS.
The side effects I had were getting pregnant!! because the metformin helped me actually ovulate because i hadnt in 6 months, we tried and wah-la pregnant!!
Besides that I have less facial hair and a much less painful period. It really helps your sugar levels as well, but of course we dont often notice that.

I hope this helps. I recommend Met to anyone who has PCOS and asks!!

Good Luck!!