Antenatal Neuroprotective Magnesium Sulfate in Very Preterm Infants and Its Association With Feeding Intolerance

Area of Science:

• Neonatal Medicine
• Perinatal Care
• Pharmacology

Background:

• Magnesium sulfate (MgSO 4 ) is used for fetal neuroprotection, but its neonatal side effects and optimal dosing are debated.
• Limited data exists on the impact of maternal MgSO 4 doses and neonatal serum magnesium (Mg) levels on short-term neonatal morbidity and mortality.

Purpose of the Study:

• To determine the impact of neonatal serum Mg levels on short-term neonatal outcomes.
• To evaluate the association between antenatal MgSO 4 exposure and neonatal morbidity.

Main Methods:

• Prospective observational study (2017-2021) of preterm infants (23-31 6/7 weeks gestation).
• Exclusion criteria included advanced resuscitation, inotropic support, major anomalies, and delayed MgSO 4 discontinuation.
• Analysis of serum Mg levels at 6 hours of life, categorizing infants into <2.5 mg/dL and ≥2.5 mg/dL groups.

Main Results:

• MgSO 4 -exposed infants had lower birth weights and higher rates of antenatal corticosteroid use and intrauterine growth restriction.
• MgSO 4 exposure was associated with increased bronchopulmonary dysplasia, prolonged ventilation, necrotizing enterocolitis, delayed enteral nutrition, and feeding intolerance.
• MgSO 4 was an independent risk factor for feeding intolerance (OR 2.13), and serum Mg levels correlated with feeding intolerance (r=0.21).

Conclusions:

• Neonatal serum Mg level is a potential predictor of immediate neonatal outcomes, especially feeding intolerance and delayed enteral nutrition.
• MgSO 4 treatment is associated with increased neonatal morbidity in preterm infants.
• Further research is needed to establish optimal serum Mg concentrations for preterm infants to maximize benefits and minimize risks.