Effects of antenatal magnesium sulfate use for neuroprotection on cardiorespiratory complications during the early neonatal period in preterm infants

Background/Aim: Antenatal magnesium sulfate (MgSO4) treatment is widely used for fetal neuroprotection in women at risk of preterm delivery. Possible adverse effects of MgSO4 include respiratory depression and delay in closure of ductus arteriosus by antagonism of calcium channels. The aim of this study was to investigate the effects of antenatal MgSO4 exposure on cardiorespiratory complications during the early neonatal period in premature infants. Methods: A retrospective cohort study was performed on 340 preterm infants born between 23 and 32 weeks of gestational age. Patients were divided into two groups according to antenatal MgSO4 exposure: The MgSO4 group (n=186) and the no-MgSO4 group (n=154). Outcomes were acute cardiorespiratory events (intubation at birth, respiratory support, and hypotension in first day of life), and hemodynamically significant patent ductus arteriosus (HsPDA). Results: Mothers in the MgSO4 group were more likely to have preeclampsia and antenatal steroid treatment, while their infants were younger in gestation and weighed less (P<0.05). Multivariate regression analysis showed that antenatal MgSO4 exposure was significantly associated with decreased mechanical ventilation (odds ratio [OR] 0.45 95% confidence interval [CI] 0.25-0.81, P=0.008), hypotension (OR 0.47, 95% CI 0.24-0.90, P=0.023) and HsPDA (OR 0.52, 95% CI 0.28-0.97, P=0.039). There was no significant association between antenatal MgSO4 exposure and intubation at birth (OR 1.06 95% CI 0.62-1.82, P=0.828). Conclusion: Among the preterm infants ≤ 32 weeks, antenatal MgSO4 was not associated with increased risk for acute cardiorespiratory events during the early neonatal period. It might have a protective role in helping with ductal closure.