Maternal obesity and degree of glucose intolerance on neonatal hypoglycaemia and birth weight: a retrospective observational cohort study in women with gestational diabetes mellitus

Gestational diabetes mellitus (GDM) is an increasing problem worldwide. Postnatal hypoglycaemia and excess foetal growth are known important metabolic complications of neonates born to women with diabetes. This retrospective cohort study aims to determine the influence of obesity and glucose intolerance on neonatal hypoglycaemia and birth weight over the 90th percentile (LGA). Data were abstracted from 303 patient medical records from singleton pregnancies diagnosed with GDM. Data were recorded during routine hospital visits. Demographic data were acquired by facilitated questionnaires and anthropometrics measured at the first antenatal appointment. Blood biochemical indices were recorded. Plasma glucose area under the curve (PG-AUC) was calculated from OGTT results as an index of glucose intolerance. OGTT results of 303 pregnant women aged between 33.6 years (29.8–37.7) diagnosed with GDM were described. Neonates of mothers with a BMI of over 30 kg/m² were more likely to experience neonatal hypoglycaemia (24 (9.2%) vs. 23 (8.8%), p = 0.016) with odds ratio for neonatal hypoglycaemia significantly higher at 2.105, 95% CI (1.108, 4.00), p = 0.023. ROC analysis showed poor strength of association (0.587 (95% CI,.487 to.687). Neonatal LGA was neither associated with or predicted by PG-AUC nor obesity; however, multiparous women were 2.8 (95% CI (1.14, 6.78), p = 0.024) times more likely to have a baby born LGA. Conclusion: Maternal obesity but not degree of glucose intolerance increased occurrence of neonatal hypoglycaemia. Multiparous women had greater risk of neonates born LGA.What is Known:•Excess foetal growth in utero has long-term metabolic implications which track into adulthood.•Neonatal hypoglycaemia is detrimental to newborns in the acute phase with potential long-term implications on the central nervous system.What is New:•Maternal obesity but not degree of glucose intolerance in a GDM cohort increased occurrence of neonatal hypoglycaemia.•Multiparous women diagnosed had greater risk of neonates born LGA.