Cytomegalovirus is the most common cause of congenital viral infection. In utero this infection is usually suspected on the basis of ultrasound findings. We present a case in which routine ultrasound examination demonstrated a decrease in fetal cephalic dimensions at 32 weeks' gestation in an asymptomatic patient. Transvaginal ultrasound revealed echogenic vessels in the thalami and lesions in the subependymal region. Suspected diagnosis of fetal cytomegalovirus infection was confirmed by positive titers of anti-cytomegalovirus-IgM antibodies in fetal blood and amniotic-fluid PCR studies. Fetal cerebral MRI demonstrated parenchymal atrophy and polymicrogyria. The parents decided to terminate the pregnancy, and necropsy confirmed the diagnosis. Suspicion of CMV fetal infection should prompt transvaginal ultrasound and fetal brain MRI.