3D ultrasound?

Larisa
I see a lot of posts with 3D ultrasounds. Did your doctor do this? If so, did you have to ask for it (as opposed to traditional 2D)? Or are these just from private ultrasound places? 
I'm high risk and just had my 7th ultrasound today (26+6) with another next week. My OB told me not to go to private places for ultrasounds as they are not medically regulated by FDA and no telling the radiation exposure that could possibly be harmful. But I'd love a 3D one - they look so amazing!