Sonographic differentiation of a large fetal cystic hygroma from the amniotic band syndrome.

An 18-year-old gravida 1, para 0 woman had an uncomplicated pregnancy until 22 weeks' gestation. Ultrasound examination revealed an abnormally shaped fetal head fixed against the placenta, minimal movement of the extremities, multiple bandlike projections traversing the uterine cavity, and bilateral pleural effusions. A diagnosis of amniotic band syndrome was suggested with subsequent termination of the pregnancy. Fetal examination revealed a large cystic hydroma, generalized edema with pericardial and pleural effusions, and Turner's syndrome. Illustrated is the difficulty in making the prenatal diagnosis of cystic hydroma and its confusion with amniotic band syndrome.