Glucose Profiles in Healthy Term Infants in the First 5 Days: The Glucose in Well Babies (GLOW) Study

Abstract

To determine postnatal changes in plasma and interstitial glucose concentrations of healthy infants receiving current recommended care and to compare the incidence of low concentrations with recommended thresholds for treatment of at-risk infants. A prospective masked observational study in Hamilton, New Zealand. Healthy, term, appropriately grown singletons had continuous glucose monitoring and repeated heel-prick plasma glucose measurements (4 in the first 24hours then twice daily using the glucose oxidase method) from birth to 120hours. The 67 infants had a mean birth weight of 3584±349g, and gestational age of 40.1±1.2weeks. The mean glucose concentrations increased over the first 18hours, remained stable to 48hours (59±11mg/dL; 3.3±0.6mmol/L)] before increasing to a new plateau by the fourth day (89±13mg/dL; 4.6±0.7mmol/L). Plasma glucose concentrations of 47mg/dL (2.6mmol/L) approximated the 10th percentile in the first 48hours, and 39% of infants had ≥1 episode below this threshold. Early term infants had lower mean glucose concentrations than those born at later gestational ages and were more likely to have episodes <47mg/dL (<2.6mmol/L) (19/32 [59%] vs 7/35 [20%]; relative risk, 3.0; 95% CI, 1.4-6.1; P=.001). Healthy infants seem to complete their metabolic transition by day 4. Many have glucose concentrations below the accepted thresholds for treatment of hypoglycemia. ACTRN:12615000986572.