Q&A 2nd trimester

I want to go for a 4D scan, as I am so curious about whom my baby takes after. But is it safe? What’s the difference between regular ultrasound and the 3D and 4D scans?

DR. PETER KOLL ANSWERS: An ultrasound machine sends out a high frequency sound wave that bounces off tissue of different density in different amounts. The wave passes straight through water with no bounce back, and water thus appears black on the ultrasound screen. Bone reflects a large amount of sound wave back and thus appears white. The other tissues in our body (and in baby’s body) reflect varying amounts of sound, depending on their density, and thus show up in varying shades of grey. The normal ultrasound gives an image in two dimensions, like an X-ray.

The 3D ultrasound takes multiple 2D pictures and reconstructs a 3D image. These 3D images are static, while 4D images move in real time. Both 3D and 4D imaging is safe for mom and baby.