GDM women in good glycemic control: which meal-related measure enhances fetal well-being?

Objective: To determine which meal-related glucose measure maximizes perinatal outcome in gestational diabetes mellitus (GDM) women who have achieved established levels of glycemic control.

Methods: Two thousand two hundred and ninety-eight GDM women were stratified by meal-related blood glucose measures: fasting (<95 mg/dL); pre-meal (< or =90 mg/dL); 2-h post-meal (< or =120 mg/dL); mean (< or =100 mg/dL). The rates of unidentified adverse outcome for composite outcome, neonatal intensive care unit (NICU), metabolic and respiratory complications and cesarean section delivery within each meal-related glucose threshold were calculated.

Results: Overall, 25-69% of large-for-gestational-age (LGA)/macrosomic infants were not identified within the recommended meal-related glucose threshold measurements. The lowest rates of unidentified morbidity were found in the pre-meal and mean blood glucose categories while the highest rates were in the post-meal category despite subjects achieving recommended levels of glycemic control. The increased rate of LGA/macrosomia within 10 mg/dL increments for each meal-related glucose category revealed that regardless of the meal-related category, the rate of LGA was significantly higher (15-25%). Logistic regressions (dependent variable= composite outcome or LGA) showed that mean blood glucose was the only significant contributor.

Conclusions: Currently recommended meal-related glucose measures do not preclude adverse fetal outcome.