Bleeding during early pregnancy.

I started bleeding everyday when I'm 7 weeks pregnant, and now that I'm 11 weeks pregnant still the bleeding goes on though it is just light bleeding. My OB advice me to take isoxilan and progestin but still I'm bleeding everyday. It's my 3rd time to get pregnant, I never had this experienced before. Six months before I got pregnant I had minor polycystic ovary syndrome.That is why I'm so worried. Is there anyone out there who could explain and help me about this? Or anyone who experienced the same thing with me?