Getting a 3D ultrasound is a similar process to having a 2D ultrasound. The main difference between the two is the technology used and the final product. 3D ultrasounds and 3D sonograms are simply a collection of 2D images put together to provide a clearer picture.
In fact, a 3D ultrasound combines thousands of pictures of the baby and then uses technology to turn the pictures into 3D ultrasound images that provide more detail of the exterior of a baby than a 2D ultrasound picture.
A 3D ultrasound is elective, and non-medical. Therefore, expecting mothers should obtain permission from their doctor before scheduling a 3D ultrasound.