Ultrasound has a critical role in the practice of obstetric. Routineultrasound examination in the first trimester appears to enable betterGestational age Assessment, early detection of clinically unsuspected fetalmalformation at a time when termination of pregnancy is possible. The aim ofthe first trimester fetal screening is to confirm the presence of a viableintrauterine pregnancy, to verify the expected delivery date by measuring theCRL, and to identify multiple gestations. Early signs of fetal malformationsshould be looked for.Finally the introduction of transvaginal US, color Doppler, 3D USrepresents a novel approach for early & accurate detection of fetalmalformations.