3D/4D Question

erin • Brailyn Rose Forck - 10.02.16💕
I am wanting to get a 4/D ultra sound done, but I've heard some doctors are against it. Could someone tell me why some doctors are against it when everyone I know that has kids & have done the 3D/4D ultra sound has a perfectly okay baby?? Have you gotten it done? Is your baby okay after you've gotten it done? Thanks!!💕