Short-term morbidities and neurodevelopmental outcomes in preterm infants exposed to magnesium sulphate treatment

Aim The aim of the study is to examine whether baseline serum Mg concentration has an impact on short-term and long-term outcomes in preterm infants exposed antenatally to MgSO4. Methods Participants included all infants admitted to the neonatal intensive care unit at <32 weeks of gestational age. Infant serum Mg concentration (iMgC) was examined immediately after birth in those exposed to maternal MgSO4. Data for short-term outcomes were collected from the infants' computerised charts. Neurodevelopmental outcomes at 6-12 months corrected age were assessed using the Griffiths Mental Developmental Scales. Results Of 197 eligible infants, 145 were exposed to MgSO4. Baseline iMgC was available for 88 infants. Mean iMgC was 3.5 ± 0.88 mg/dL (1.6-5.7 mg/dL). Baseline iMgC was not associated with an increased risk for neither early morbidities nor adverse long-term outcome. However, iMgC above the mean (>3.5 mg/dL) was associated with significantly lower scores on locomotor (P = 0.016) and personal-social (0.041) scales in the first year of life. Conclusions In a cohort of preterm infants antenatally exposed to MgSO4, elevated baseline iMgC (>3.5 mg/dL) was associated with lower locomotor scores. Further research is needed in order to study the relationship between supra-physiologic iMgC and its effect on the developing brain.