Association between magnesium sulfate for threatened preterm labor and symptomatic patent ductus arteriosus in preterm newborns

Abstract

 We investigated the association between magnesium sulfate and symptomatic patent ductus arteriosus（PDA）in 121 singleton cases of preterm delivery treated with magnesium sulfate between 2020 and 2022. The study factors were as follows: chorioamnionitis, mode of delivery, number of weeks of delivery, birth weight, drugs used, maternal blood magnesium（Mg）level, cord blood Mg level, and duration of magnesium sulfate administration. The duration of magnesium sulfate administration（weeks）was 1（0-6）for symptomatic PDA and 3（0-14）for non-symptomatic PDA. Factors associated with symptomatic PDA were preterm delivery at <28 weeks’ gestation（p<0.01, OR25.5）, low birth weight <1, 500 g（p<0.01, OR31.5）, chorioamnionitis（p=0.02, OR3.9）, cesarean delivery（p=0.03, OR4.5）, cord blood Mg level（p=0.02, OR3.0）, and duration of magnesium sulfate administration（p<0.01, OR0.8）. A correlation was observed between maternal blood Mg levels and cord blood Mg levels. In multivariate analysis adjusted for the number of weeks of delivery, cord blood Mg level and duration of magnesium sulfate administration were not significantly associated with symptomatic PDA（p=0.2, OR2.3）, （p=0.4, OR1.2）. Treatment of threatened preterm labor with magnesium sulfate may not increase the risk of symptomatic PDA under appropriate doses.