Real-time 2D ultrasound is the gold standard in examining fetal anatomy. 3D ultrasound is a technical advance that give complementary information to that provided by the 2D ultrasound. 3D volumes can provide maximum information in a very limited scanning time, thus reducing examination time. Faster acquisition time and improvement of the resolution of the 3D probe could overcome current limitations and make feasible the routine use of 3D US in early pregnancy. In patients at risk for carrying a fetus with a specific heritable disorder, the routine obstetric examination must be supplemented by a directed search for the expected phenotypic abnormalities. Suggested an approach to the diagnosis of skeletal dysplasias through an organized examination of the fetal skeleton (Figure). The specific diagnosis of a skeletal dyspalsia in utero requires familiarity with a complex algorithm of ultrasonographic features.