When is the best time to have a 4D?

This optional service is best performed around 27 to 30 weeks gestation and affords an opportunity to obtain three and four dimensional images of your baby, particularly of it’s face and heart.  The study provides an opportunity for you to see your child’s growth and development early in the third trimester and to look for heart and facial defects that might not be apparent in the routine ultrasound offered at 18 weeks of gestation.