Effect of maternal diabetes on the fetal exocrine pancreas.

To test the hypothesis that fetal pancreatic exocrine and endocrine function are stimulated in parallel in the diabetic pregnancy, 68 mothers with gestational and pregestational diabetes who underwent amniocenteses after 34 weeks' for the evaluation of fetal lung maturity were enrolled. Amniotic fluid specimens were analyzed for C-peptide and trypsin content. Amniotic fluid specimens were obtained from 92 non-diabetic women undergoing amniocenteses for lung maturity, preterm labor, or premature rupture of membranes. Groups were compared using the Wilcoxon rank-sum test, Kruskal Wallis rank sum test, and Spearman's rank correlation test. C-peptide amniotic fluid concentrations were significantly greater in diabetics (median 0.6 ng/ml) than non-diabetics (median 0.4 ng/ml, P= 0.0001), in pregestational (median 0.6 ng/ml) vs. gestational diabetics (median 0.4 ng/ml, P = 0.006), and greater in proportion to severity of disease according to diabetic class (A1 = 0.4 ng/ml, A2 = 0.55 ng/ml, B = 0.6 ng/ml, C = 0.7 ng/ml, D = 0.85 ng/ml, P = 0.04). No significant differences were detected in amniotic fluid trypsin between the diabetic and non-diabetic or the gestational and non-gestational diabetic groups. There was no correlation between C-peptide and trypsin within the diabetic groups. Stimulation of the exocrine and endocrine pancreas does not occur in parallel in the fetus of the diabetic mother. Although originating as a single organ, pancreatic exocrine and endocrine functions are distinct in both physiologic and pathologic conditions.