An experience with dystocia due to fetal ascites is described. It was necessary to perform intrauterine fetal abdominal paracentesis to complete the delivery. The ascites was associated with a diffuse hepatic developmental anomaly interpreted as a form of polycystic disease without cysts. Associated anomalies included cystic lung and a very rare variety of pulmonary arteriovenous fistula. The structural abnormality in the liver, though in an exceptionally undifferentiated stage, belongs to the category of so-called congenital hepatic fibrosis, which, in turn, is a noncystic variant of congenital polycystic disease. Theoretical aspects of the pathogenesis of the ascites are discussed. A new term, portal dysplasia of the liver (polycystic disease without cysts), descriptively adequate to embrace all of the structural variations of this developmental hepatic abnormality, is suggested.