Which Congenital malformation of the fetus can be diagnosed in first trimester by ultrasound?

Ans. A. AnencephalyUltrasound can be used to detect anencephaly as early as 10 weeks' gestation. With an abnormal head/trunk ratio and abnormally large orbits, the absence of the superior vault is associated.The length of crown-rump is normal in most anencephalic fetuses.