Risk of hypoglycemia by anthropometric measurements in neonates of mothers with diabetes.

Macrosomia in neonates of diabetic women is a risk factor for neonatal hypoglycemia, with an over-risk for asymmetric macrosomia. This study aimed to study the association between anthropometric measurements and hypoglycemia in neonates of mothers treated for gestational diabetes. This is a secondary analysis of the INDAO trial study conducted between May 2012 and November 2016 in 13 French tertiary care university hospitals in 890 pregnant women with gestational diabetes treated with either insulin or glyburide. Neonatal anthropometric measurements were birthweight and weight-length ratio (WLR, defined as birth weight/length). Neonatal hypoglycemia was defined as capillary blood glucose below 36 mg/dL (2 mmol/L) or below 45 mg/dL (2.5 mmol/L) associated with clinical signs after 2 h of life. Their relationships were modeled with logistic regressions using fractional polynomials. Extreme categories of birthweight or WLR adjusted for gestational age at birth and sex were defined as Z-score <  -1.28 or > 1.28. These categories were compared to Z-score between -1.28 and 1.28 by estimating odds ratios and confidence intervals for neonatal hypoglycemia. Neonatal hypoglycemia occurred in 9.1% of cases. The relationship between birthweight and WLR Z-scores and neonatal risk of hypoglycemia adjusted for maternal treatment was a U-shaped curve. Adjusted odds ratios for the risk of hypoglycemia were 9.6 (95% CI 3.5, 26.8) and 2.3 (95% CI 1.1, 4.9) for WLR Z-score below -1.28 and above 1.28, respectively, compared with WLR Z-score between -1.28 and 1.28.    Conclusion: Birthweight Z-score was associated with the risk of neonatal hypoglycemia in neonates from mothers treated for gestational diabetes. The risk of neonatal hypoglycemia was increased for both extreme birthweight Z-scores, regardless of maternal treatment. Small for gestational age neonates of diabetic mothers require special attention for the risk of neonatal hypoglycemia. What is Known: • Macrosomia in neonates of diabetic women is a risk factor for neonatal hypoglycemia, with an over-risk for asymmetric macrosomia. Few retrospective studies have assessed the risk for neonatal hypoglycemia among small for gestational age neonates born to diabetic mothers. What is New: • The risk of neonatal hypoglycemia among neonates of diabetic mothers increased for both low and high weight-length ratio, regardless of maternal medicinal treatment, gestational age at birth, and sex of the newborn.