Fluid status changes during the transition in infants of diabetic mothers

In animal and human neonates, expansion of the extracellular fluid volume is associated with "wet" lung and poor respiratory outcomes. To define fluid status changes during the transition from fetal to neonatal life in infants of diabetic mothers (IDM), we conducted a single-centre (Policlinico Abano Terme, Abano Terme, Italy) study of 66 IDM and a 1:2 matched control group from January 1 to September 30, 2020. Fluid status changes were assessed by computing Δ Hct from umbilical cord blood at birth and capillary heel Hct at 48 h, accounting for body weight decrease. IDM presented with significantly lower cord blood Hct levels in comparison to controls (47.33 ± 4.52 vs 50.03 ± 3.51%, p < 0.001), mainly if delivered by elective cesarean Sect. (45.01 ± 3.77 vs 48.43 ± 3.50%, p = 0.001). Hct levels at 48 h were comparable (55.18 ± 5.42 vs 54.62 ± 7.41%, p = 0.703), concurrently with similar body weight decrease (- 217.21 ± 113.34 vs - 217.51 ± 67.28 g, p = 0.614). This supports significantly higher ∆ Hct in IDM (5.13 ± 5.24 vs 7.29 ± 6.48, p < 0.01) and extra circulating fluid loss of 2-3%.Conclusion: Gestational diabetes is associated with an excess of circulating fluids during the transition from fetal to neonatal life, challenging the current assumption that is per se at risk of wet lung. What is Known: • In neonates, evidence suggests that expansion of the extracellular fluid volume prior to the postnatal diuresis is associated with poor respiratory outcomes. What is New: • Gestational diabetes is associated with an excess of circulating fluids during the transition from fetal to neonatal life, challenging the current assumption that is per se at risk of wet lung.