Guidelines for Intravenous Magnesium Sulfate for Neuroprotection in Preterm Pregnancy

Indications and Timing

Magnesium sulfate should be administered for fetal neuroprotection when preterm delivery is anticipated before 32 weeks' gestation, as it significantly reduces the risk of cerebral palsy without increasing mortality, according to the American College of Obstetricians and Gynecologists 1, 2, 3, 4
Magnesium sulfate is recommended for fetal neuroprotection when delivery is anticipated before 32 weeks' gestation, as stated by the American College of Obstetricians and Gynecologists 4
Although data specific to the periviable period (22-25 weeks) are limited, magnesium sulfate prophylaxis is still recommended if delivery of a potentially viable infant is anticipated, as suggested by the American College of Obstetricians and Gynecologists 1, 2, 3

Antenatal corticosteroids should be administered between 24+0 and 34+0 weeks of gestation when preterm delivery is anticipated, as recommended by the American College of Obstetricians and Gynecologists 4
In cases of fetal growth restriction with absent end-diastolic flow, delivery should be considered by 34 weeks gestation, according to the American Heart Association 5
In cases of reversed end-diastolic flow, delivery should be considered by 30 weeks gestation, as stated by the American Heart Association 5

For women with preeclampsia, magnesium sulfate serves dual purposes: prevention of eclamptic seizures and fetal neuroprotection, as noted by the American Heart Association 6 and the European Association for the Study of the Liver 7

Premature newborns exposed to maternal magnesium sulfate therapy may have high magnesium levels in the first days of life, and monitoring is essential as these infants have limited ability to excrete excessive magnesium due to low postnatal glomerular filtration rates during the first week of life 8, 9
Magnesium intake must be carefully managed in newborns whose mothers received magnesium sulfate before delivery 9