Exercising while pregnant?

I had only recently begun exercising before I found out I was pregnant so I was in no means in shape and I had no routine yet. I haven't spoken to my doctor about it yet but I'm going to see a health educator on Wednesday. My doctor's office requires seeing a health educator before your first prenatal/OB appointment) Well, my last two pregnancies ended in miscarriage so I'm a little scared to be foing to the gym because I don't know how much I should be doing. What have your doctor's recommended for you while pregnant? For reference I was going to the gym 4 times a week 2 hours a day for only 2 weeks before I found out I was pregnant.