IN-UTERO DEFECATION OF THE NONDISTRESSED FETUS - A ROENTGEN STUDY IN THE GOAT

An experimental study was performed to investigate gastrointestinal mo tility and meconium passage, with simultaneous blood gas measurements, in the fetuses of eight pregnant goats at 110 to 114 days' gestation (full term, 147 to 155 days). With the goats under halothane anesthesi a, a nasogastric tube and a heparinized central venous catheter were i nserted into the fetuses. 24 hours after surgery, 10 mL of gastric jui ce from the fetus was replaced with a nonhydrosoluble contrast medium, and serial roentgenograms and blood samples (for pH. PO2, and PCO2 me asurement) were taken every 4 hours. All fetuses began to pass the con trast medium into the amniotic cavity within 16 to 22 hours, and centr al venous blood gas values were normal. The results of this study sugg est that the fetus, which urinates routinely, also defecates routinely into the amniotic cavity, even in the absence of distress. The increa sed incidence of meconium staining in fetal distress conditions may be indicative of impaired clearance of amniotic fluid. Copyright (C) 199 4 by W.B. Saunders Company