Like regular ultrasounds, 3D and 4D ultrasounds use sound waves to create an image of your baby in your womb. What's different is that 3D ultrasounds create a three-dimensional image of your baby, while 4D ultrasounds create a live video effect, like a movie you can watch your baby smile or yawn. Parents often want 3D and 4D ultrasounds. They let you see your baby's face for the first time. Some doctors like 3D and 4D ultrasounds because they can show certain birth defects, such as cleft palate, that might not show up on a standard ultrasound. Studies suggest that 3D and 4D ultrasounds are safe. Plus, the images can help doctors spot a problem with your baby and make it easier for them to explain it to you.
For an abdominal ultrasound, you'll lie down and a technician will put a certain gel on your belly. This helps carry the sound waves. Then the technician will hold a probe against your belly and move it around to get an image.