[Role of the amniotic fluid in gastroschisis. An experimental study]

The short and thick bowel found in gastroschisis has been attributed to contact with amniotic fluid, among other factors. We designed an original animal model in order to isolate the effect of amniotic fluid on the fetal bowel. We created experimental gastroschisis in fetal rabbits. Extruded bowel was kept out of the amniotic sac in half of the operated fetuses. At term, seven days after surgery, 21 surviving fetuses--12 intra-amniotic (GIA) and nine extra-amniotic (GEA)--and 16 control littermates were harvested for study. Five parameters were measured in each animal: body weight, intestinal weight, intestinal length, bowel diameter and bowel wall thickness. We found no statistically significant difference in body weight, intestinal weight or bowel wall thickness. An enormous difference was found in intestinal length among the three groups. Bowel diameter was significantly different in the extreme groups (GIA and controls), with the intestine being more dilated in GIA than in GEA and controls. Gastroschisis in the absence of amniotic fluid has not been as damaging to the fetal intestine as "natural" intraamniotic gastroschisis.