When did you go to first prenatal appt?

I'm hesitant on going. I've had three miscarriages last year, all around 6 weeks. Am 4 weeks today and although we are excited, of course we are nervous too. I'm worried. Since there is nothing they can do to prevent miscarriage and they won't be able to hear a heartbeat until 6 weeks, which we never did on any of the 3. Some Drs won't even see you until 8 weeks. Is there any harm in waiting?