Insulin glargine compared with Neutral Protamine Hagedorn insulin in the treatment of pregnant diabetics

Objective: To compare maternal and neonatal outcomes of pregestational and gestational diabetics treated with insulin glargine versus Neutral Protamine Hagedorn (NPH) insulin.

Methods: A retrospective cohort study examining outcomes from pregestational and gestational diabetics treated with either insulin regimen. Comparisons were made using the t-test for continuous data and the Chi-square or Fisher's exact test for categorical data.

Results: Fifty-two pregnant women treated with insulin glargine were compared with 60 pregnant women treated with NPH. No significant differences in rates of maternal complications were noted. No significant differences in neonatal outcomes for gestational diabetics were noted. Among pregestational diabetics treated with insulin glargine, significantly fewer macrosomic infants (relative risk [RR], 0.38; 95% confidence intervals (CI), 0.17-0.87; p = 0.04) and lower rates of neonatal hyperbilirubinemia (RR, 0.27; 95% CI, 0.07-0.98; p = 0.05) were noted when compared with those treated with NPH. There were no cases of neonatal hypoglycemia in pregestational diabetics treated with glargine; however, 25% of infants born to mothers treated with NPH experienced hypoglycemia (p = 0.01). No fetal anomalies or deaths were observed in either treatment group.

Conclusion: Insulin glargine use during pregnancy is not associated with increased maternal or neonatal morbidity compared with NPH insulin. Among pregestational diabetics, insulin glargine use was associated with lower rates of macrosomia, neonatal hypoglycemia and neonatal hyperbilirubinemia.