A newborn to a mother on magnesium sulfate therapy would be at risk for which finding related to the therapy?

A newborn to a mother on magnesium sulfate therapy would be at risk for which finding related to the therapy?

• A. Hypotension
• B. Hyperreflexia
• C. Hypoglycemia
• D. Seizures

Answer: (A)

Magnesium sulfate acts as a CNS depressant and a smooth‑muscle relaxant, and it crosses the placenta, so the newborn can be exposed to elevated magnesium levels. In the neonate, this exposure can dampen neuromuscular activity and cause relaxation of vascular smooth muscle, leading to reduced systemic vascular resistance and lower blood pressure. That makes hypotension the most likely finding related to the therapy in a newborn. Hyperreflexia would be unlikely because magnesium suppresses neuromuscular excitability, not increases it. Seizures are prevented by magnesium, not caused by it, and hypoglycemia isn’t a typical direct effect of magnesium exposure.

Magnesium sulfate acts as a CNS depressant and a smooth‑muscle relaxant, and it crosses the placenta, so the newborn can be exposed to elevated magnesium levels. In the neonate, this exposure can dampen neuromuscular activity and cause relaxation of vascular smooth muscle, leading to reduced systemic vascular resistance and lower blood pressure. That makes hypotension the most likely finding related to the therapy in a newborn.

Hyperreflexia would be unlikely because magnesium suppresses neuromuscular excitability, not increases it. Seizures are prevented by magnesium, not caused by it, and hypoglycemia isn’t a typical direct effect of magnesium exposure.