Metformin Hydrochloride and periods

I've been taking Metformin on and off for the past year, and I honestly think it's great now that I'm taking it regularly and eating right. I was prescribed Metformin for my PCOS and IR.

When I was first prescribed Metformin, I thought it was causing my hypoglycemia. I didn't eat right when I first began Metformin. I didn't eat horribly, but I wasn't eating right. It'd make me shaky, dizzy, and weak, so I wasn't taking it as prescribed and eventually stopped taking it.

I began exercising regularly and lost some weight while off it, but noticed that stomach fat seemed to go away faster while on it even when I'd stopped exercising. I was only taking 500mg a day then. One thing that it fixed right away was my period. I used to only get my period every three months or so, but the second I began Metformin, it did wonders to regulate my period. I was going through personal issues and again stopped taking it, but then was prescribed 1,000mg a day.

I was determined to take it as prescribed this time and started out slow with 500mg. Even though the previous times I'd never had any reaction to it, I had very bad stomach issues. I kept taking it regardless, and they eventually went away. I upped it to the 1,000mg then. I improved my eating habits by including more low GI and fiber-rich foods and ate more regularly throughout the day.

My periods are regulated, and I haven't had any hypoglycemic episodes. My stomach fat is going down, especially now that I've added in Yaz, and I'm hoping, along with improved diet and exercise, that this helps me lose these last 15 pounds, particularly the belly fat.

If someone can answer this question for me that would be very appreciated.

1. Does this med cause weight gain?
2. Does this Poloystic Hormon Syndrome ever cure, does is cause infertility?
I'm trying to have a child, and i'm concerned about that issue.

The only side affect i have was diarrhea.....It hasn't continued, but sometimes a little gas.