Please help new PCOS diagnosis

Hi, so I have been having periods every other week for two months now, and I went to my OBGYN this weeks. We drew blood and were told to wait 3 weeks for an ultrasound. My blood work came back the next day and my progesterone was <0.5...there was some other abnormalities that showed that I more than likely have PCOS. So my OBGYN decided to put me on 500mg metformin. I was wondering if anyone else had low progesterone with PCOS that was fixed with metformin only?