RESUMO
AIM: To determine risk factors associated with neonatal hypoglycaemia and hyperbilirubinaemia, and assess their impact on neonatal outcomes in pregnancies complicated by gestational diabetes mellitus (GDM). METHODS: Retrospective review investigating all pregnancies complicated by GDM at Campbelltown Hospital (Sydney, Australia) between 1 January 2013 and 31 December 2015. Main outcomes measured were neonatal hypoglycaemia (capillary glucose levels < 1.8 mmol/l) and hyperbilirubinaemia (total serum bilirubin levels greater than age-appropriate thresholds for phototherapy). Adjusted odds ratios [95% confidence interval (CI)] are shown, calculated by multivariable logistic regression. RESULTS: Some 60 (7.8%) infants developed hypoglycaemia, 58 (7.5%) developed hyperbilirubinaemia and 13 (1.7%) developed both. Risk of developing hypoglycaemia increased 1.8-fold (95% CI 1.3-2.6, P < 0.001) per gestational week at GDM diagnosis, 1.1-fold (95% CI 1.0-1.3, P = 0.04) per mmol/l maternal fasting glucose, 6.2-fold (95% CI 2.6-16.2, P < 0.001) with maternal history of macrosomia, 10.8-fold (95% CI 4.1-27.6, P < 0.001) with multiple pregnancy and 1.1-fold (95% CI 1.0-1.3, P = 0.04) per gestational week at birth. Risk of hyperbilirubinaemia increased with multiple pregnancy (26.4; 95% CI 11.7-59.7, P < 0.001), and 1.5-fold (95% CI 1.1-2.1, P = 0.01) per gestational week at GDM diagnosis. Hypoglycaemia was associated with a 2.8-fold (95% CI 1.1-7.1, P = 0.03) increased risk of macrosomia, a 5.4-fold (95% CI 1.1-27.3, P = 0.04) excess risk of shoulder dystocia and a 6.4-fold increased risk of 5-min APGAR ≤ 7 (95% CI 1.2-1.7, P < 0.001). Hyperbilirubinaemia was associated with an excess risk of polycythaemia (packed cell volume > 0.6; 97.1, 95% CI 38.9-241.5, P < 0.001). CONCLUSIONS: Neonatal hypoglycaemia and hyperbilirubinaemia largely occur in different pregnancies. Both are associated with earlier GDM diagnosis; however, hypoglycaemia is more associated with maternal glycaemia and its sequelae, and hyperbilirubinaemia is associated with polycythaemia.