Hello Donna......
So sorry about your loss

From my experience with met, it does(in most cases)reduce the risk of m/c and that is why most Drs like you to stay on it until your 12th week of pregnancy some keep you on longer.
I have type 2 diabetes and I am on 1500 mgs of glucophage(met) daily to help with my PCOS too.
I got pregnant (using IUI) in July of 2002 and m/c at 6 weeks. I did not know any better and I had quit ALL meds, including my met.......once I got to talking to the nurse, I told her I quit taking met and she asked why....I said noone in your office told me any different and I thought any drugs may harm the baby so I stopped.
Peggy(the nurse) explained that met helps reduce the risk of m/c.......I then felt as if it was all my fault

I then got pregnant (using IUI again) with Bryan in Nov of 2002, I stayed on it until 12 weeks
Best of luck with #2, whenever that may be.
Take care,
Beth