목적: We aimed to assess whether antenatal magnesium sulfate (MgSO4) therapy given to women with premature rupture of membranes (PROM) remote from term could prolong pregnancy and improve maternal outcomes, perinatal outcomes, and neurodevelopmental outcomes. 방법: We included 184 singleton pregnancies with PROM remote from term (23-31 weeks) between 2005 and 2013. These women were divided into two groups: one group that received MgSO4 therapy for tocolysis (MgSO4 group) and the second group that received no tocolytic therapy (No MgSO4 group). 결과: The latency period was significantly longer in the MgSO4 group (p=0.0017). Antenatal MgSO4 therapy was significantly associated with decreased stillbirth (p=0.0012) and perinatal mortality (p=0.0375). In the subgroup analysis by gestational age at diagnosis of PROM, the subgroup of PROM at 23-27 weeks’ gestation showed significantly reduced the risk of intraventricular hemorrhage (IVH: 20.4% vs 58.3%; RR, 0.35; 95% CI, 0.17 to 0.71) and periventricular leukomalacia (PVL: 27.8% vs 58.3%; RR, 0.48; 95% CI, 0.25 to 0.91) in the MgSO4 group compared with no MgSO4 group. And the incidence of developmental delay in the subgroup of 23-27 weeks’ gestation was significantly lower in the MgSO4 group (6.5% vs 36.4%; RR, 0.18; 95% CI, 0.05 to 0.69). A similar trend was observed for cerebral palsy, with 22.2% of unexposed children affected compared with only 7.7% of exposed children. However, there were no significant differences in the development of IVH, PVL, developmental delay, and cerebral palsy between the two groups for patients in the subgroup of 28-31 weeks’ gestation. 결론: Antenatal MgSO4 in women with PROM remote from term could prolong pregnancy, allowing for corticosteroid benefit without significant increase in the risk of neonatal morbidities and chorioamnionitis. Moreover, MgSO4 therapy had fetal neuroprotective effects for neonatal IVH and PVL, and for developmental delay in infancy and cerebral palsy in early childhood, especially in women with PROM at 23-27 weeks’ gestation.