Does fetal gut obstruction cause hydramnios and growth retardation?

In order to study the effects of impaired fetal intestinal absorption of amniotic fluid, two series of neonates (551 from Liverpool and 172 from Rome) with different types of congenital gut obstruction were divided into two groups and compared. Group A consisted of patients with complete obstruction at or above the proximal jejunum (within 15 cm of the ligament of Treitz). Patients of group B had either incomplete obstruction at group A level or either incomplete or complete obstruction at a lower level. Maternal hydramnios and fetal growth retardation rates were found to be significantly higher in group A than in group B. Maternal hydramnios was associated with an increased prematurity rate (P less than .001). Fetal growth retardation was not related to the presence of additional anomalies. In group A growth retardation was more frequent in babies born after 37 weeks of gestation (P less than .05). No differences were found between the Liverpool and Rome series of patients. These findings suggest that fetal gut function not only contributes to the control of amniotic fluid volume but also, in the final stages of pregnancy, to normal fetal growth. Maternal hydramnios may be the cause of premature delivery of fetuses with upper gut obstructions.