Phototherapy-induced Hypomagnesemia in Term Newborns with Jaundice

Background and Objectives: Neonatal jaundice is prevalent in 60% of term and 80% of preterm neonates, with 6.5% experiencing readmission. Phototherapy is a safer treatment but can cause electrolyte imbalances. This study was conducted to know the prevalence of hypomagnesemia among term neonates receiving phototherapy and any possible correlation between duration of phototherapy and severity of hypomagnesemia. Materials and Methods: A year-long study (September 2020–September 2021) in the pediatrics department focused on 73 term newborns with hyperbilirubinemia requiring phototherapy. Maternal and birth data were recorded, and serum bilirubin, magnesium, and calcium levels were monitored before starting phototherapy, 12 h, 24 h, and after stopping phototherapy. Results: A study enrolled 73 full-term neonates with neonatal jaundice, with 58.9% of males and 41.1% of females. The highest number of newborns were in gestational age groups of 38–39 weeks, while the lowest were in 40–41 weeks. The study found that the calcium and magnesium values at admission were within normal limits with a mean value of 9.13 mg/dL and 2.11 mg/dL, respectively, and the newborns presented with jaundice at a mean age of 2.4 days. The mean duration of phototherapy required was 30.16 h. The prevalence of hypomagnesemia increased with the duration of phototherapy ( P < 0.002). Conclusion: The study observed a significant drop in magnesium levels after phototherapy in term neonates with jaundice, with 8.2% developing asymptomatic hypomagnesemia. None showed symptoms such as seizures, tachycardia, or arrhythmias.