Fetus with asymmetric parietal encephalocele, and hydrops secondary to laryngeal atresia.

We describe a fetus with an asymmetric, nonmidline, parietal encephalocele that appeared to result from "expulsion" through the center of the membranous bone; the fetus also had laryngeal atresia, which caused pulmonary overdistension (fetal Valsalva maneuver) with consequent hydrops fetalis. A common cause and clear pathogenetic relationship between these anomalies is not apparent.