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.

Management of the Rh-sensitized mother.

The approval by the FDA of Rh immune globulin in 1968 led to a decrease in the incidence of Rh isoimmunization. As a result, fewer cases are seen by both the perinatologist and neonatologist. Prompt identification and early referral of the isoimmunized mother to a tertiary center will facilitate optimal management incorporating the latest techniques. In selected clinical situations, the less invasive technique of amniocentesis can be offered in place of fetal blood sampling for Rh D typing. In the anemic fetus requiring intrauterine transfusions, delivery is the goal once lung maturity is documented. As described elsewhere in the issue, recent improvements in neonatal care have facilitated management of complications not seen in the fetus but potentially critical in the neonate.

Alternate methods of first-trimester diagnosis.

Fetal medicine is a new discipline that emerged out of the expansion of modern technology. Evaluation of the fetus heretofore was not possible except by indirect methods. Pregnancy management focused primarily on the care of the mother with the expectation that the fetus would be an indirect beneficiary. Our present-day approach to pregnancy and prenatal evaluation has been altered by the introduction of new techniques such as ultrasound, amniocentesis, and CVS, which have made the fetus and its intrauterine environment accessible. Improvements in ultrasonographic equipment have allowed for better visualization of the fetus, earlier detection of structural anomalies, and facilitation of the performance of invasive procedures. The recent introduction of CVS represents a major step toward achieving the goal of early diagnosis. Prevailing experience has demonstrated that it is a relatively safe and reliable procedure with a low complication rate. Early amniocentesis may be considered as an alternative to CVS when the latter is not advisable, although future studies are needed to accurately estimate the procedure-related risks (Table 5). Transcervical endoscopy allows a more detailed appreciation of fetal anatomy, although its role in clinical practice remains to be defined. Biochemical markers such as alpha fetoprotein, unconjugated estriol, and hCG, alone and in combination, have been studied regarding their potential to predict chromosomal abnormalities. Today there is a changing trend in prenatal diagnosis with women requesting more information about their unborn child and expecting such information earlier in gestation. The goal of prenatal diagnosis has been directed toward earlier detection to reduce the anxiety of waiting and permit the safer option of first-trimester termination of pregnancy.