Ultrasound.

malaking advantage ang CAS momsh kc nkikita if may abnormality si baby..nkikita din kung may possibleng complications bah..sinisilip kc heart ni baby..brain..etc if it's developing well...the ob sonologist also measures the body parts of the baby kung tama ba based on the age of gestation. ang 3d ultrasound kc mainly pra makita lng external features ni baby. you can do both naman..pero if needed to choose only 1.. mag CAS ka na