The effect of carbohydrate intolerance on neonatal birth weight in pregnant women without gestational diabetes mellitus.

BACKGROUND

There is still no consensus on screening, threshold levels and treatment of gestational diabetes mellitus. Furthermore, the importance of a positive 50-g glucose screening test in patients who had a negative 100-g oral glucose tolerance test remains controversial. We investigated the impact of the 50-g glucose screening test results on neonatal outcome in pregnant women with uncomplicated pregnancies, who had no risk factors according to ACOG criteria.

PATIENTS AND METHODS

Three hundred eighty-six pregnant women with singleton pregnancies were prospectively screened with 50-g glucose challenge test between 24 and 28 weeks. If the test result was >140 mg/dl, a 100-g 3-hour oral glucose tolerance test was performed. Patients with a positive screening test, but not diagnosed as gestational diabetes mellitus constituted the study group, and patients with a negative screening test constituted the control group. Cesarean rates, neonatal birth weights and complications were compared between these groups.

RESULTS

The cesarean delivery rates were not statistically different between the study and control groups (8.3% vs. 6.4%, P>0.05). The rates of macrosomic births were 10.0% in the study group, and 6.4% in the control group (P>0.05), but the mean birth weight (3451.67 +/- 355.70 g) in the study group was significantly higher than the mean birth weight (3296.29 +/- 365.14 g) in the control group (P=0.003). Neonatal hypoglycemia and hyperbilirubinemia was also encountered more often in babies of pregnant women with a positive 50-g glucose challenge test but negative 100-g glucose tolerance test.

CONCLUSION

Because of similarities with gestational diabetes mellitus on the basis of perinatal outcomes, the non-diabetic pregnant women with 50-g glucose screen test result over 140 mg/dl but a negative 100-g OGTT should be followed closely.