Effect of Antenatal Magnesium Sulfate Exposure on Patent Ductus Arteriosus in Premature Infants

Abstract

Objective Magnesium sulfate (MgSO4) provides effective fetal neuroprotection. However, there is conflicting evidence regarding the association between antenatal MgSO4 exposure and patent ductus arteriosus (PDA). Thus, herein, we aimed to evaluate the association between antenatal MgSO4 exposure and PDA. Study Design Preterm infants born between 240/7 and 316/7 weeks of gestation were included in this retrospective study. Infants who died within the first 72 hours of life and those with significant congenital anomalies were excluded from the study. Echocardiographic and clinical assessment parameters were used to define PDA and hemodynamically significant PDA (hsPDA). Treatments were planned according to the standard protocols of the unit. The following data were collected from hospital medical records: perinatal characteristics, neonatal outcomes, detailed PDA follow-up findings, and maternal characteristics including MgSO4 exposure and doses. Results Of the 300 included infants, 98 (32.6%) were exposed to antenatal MgSO4. hsPDA rates were similar in the infants exposed and not exposed to antenatal MgSO4, when adjusted for antenatal steroid administration, gestational age, and birth weight (OR: 1.6, 95% CI: 0.849–3.118, p = 0.146). The rates of PDA ligation and open PDA at discharge were similar between the groups. A cumulative MgSO4 dose of >20 g was associated with an increased risk of hsPDA (crude OR: 2.476, 95% CI: 0.893–6.864, p = 0.076; adjusted OR: 3.829, 95% CI: 1.068–13.728, p = 0.039). However, the cumulative dose had no effect on the rates of PDA ligation or open PDA at discharge. Rates of prematurity-related morbidities and mortality were similar between the groups. Conclusion Although antenatal MgSO4 exposure may increase the incidence of hsPDA, it may not affect the rates of PDA ligation or open PDA at discharge. Further studies are required to better evaluate the dose-dependent outcomes and identify the MgSO4 dose that not only provides neuroprotection but also has the lowest risk of adverse effects. Key Points