2-3 at my Dr's office one to confirm and one for gender and growth and occasionally one at the end to determine weight and make sure they are head down..

I got one when I first found out I was pregnant at my first appointment (14 weeks) then my anatomy scan at 19 weeks then I had one at 29 weeks then most recently at 32 weeks but that one was actually just because they mis scheduled me, it wasn't actually supposed to be an ultrasound but they did it for me anyways lol

I'm high risk and still don't get them that often

I only get two. one dating around 8 weeks and one anatomy scan around 20 weeks.
any more would be pay for third party places.

with my first I only got one but with this one I've had 4 due to some issues

I think your normally suppose to get 3-4