Association between Cerebral Palsy or Death and Umbilical Cord Blood Magnesium Concentration

Objective This study aims to evaluate whether magnesium sulfate (MgSO₄) infusion at the time of delivery or magnesium cord blood concentration is associated with cerebral palsy (CP) or death diagnosed by the age of 2 years. Methods Secondary analysis of data from a randomized trial of MgSO₄ versus placebo for prevention of CP or death among offspring of women with anticipated preterm delivery. This study cohort included singleton, nonanomalous fetuses, whose mothers received MgSO₄ as neuroprophylaxis. The primary outcomes were CP or death diagnosed by the age of 2 years. Results A total of 936 neonates (93 with CP or death, 843 controls) were included in the analysis. Infants in the group with CP or death had MgSO₄ infusing at delivery at a similar frequency to that of controls (49 [52.7%] vs. 463 [54.9%], p = 0.68). Mean concentrations of cord blood magnesium, available for 596 neonates, also were not different between the two groups (2.7 ± 0.9 vs. 2.6 ± 0.9 mEq/L, p = 0.66, respectively). Multivariable analyses did not alter these findings. Conclusion Among the offspring of women exposed to MgSO₄, in utero, neither MgSO₄ infusion at the time of delivery nor magnesium cord blood concentration is associated with CP or death.