Has anyone ever used this?

So I recently experienced a miscarriage and now I have been spotting for a little over a month straight with a period in the middle. My periods have been normal my whole life up until January of this year. I have been to the dr and have had both an ultrasound and a transvaginal ultrasound as well and everything came back looking normal not strange. My dr is thinking that maybe my body is being kinda like PCOS with how my hormones are acting, same with my period. Well today he put me on 500mg Metformin twice a day. Have anyone used this and had helped with fertility? Just don’t know what to think.