I think every practice may do it a little differently.
My hospital does a pregnancy test at the first appointment & prescribes prenatal vitamins. The second appointment is known as OB Enrollment where you just fill out a bunch of paperwork, and 3rd appointment is OB Intake where you meet with a nurse who goes over what kind of care the hospital provides throughout prenatal care, as well as labor and delivery, plus a dating scan. My fourth appointment will be at the end of this week, and this will be the first time I'm meeting with my widwife for a regular prenatal appointment at 12 weeks pregnant.