Background: Magnesium (Mg) infusion is first-line for seizure prophylaxis in preeclampsia with severe features (PESF). Guidance is lacking regarding utility of an additional course of Mg for disease exacerbation following completion of an initial course. We aimed to determine the national trend among academic institutions for administration of a second course of Mg in patients with an exacerbation of PESF. Methods: A REDCap survey querying response to clinical scenarios related to Mg administration was sent to Maternal-Fetal Medicine program directors (or surrogate if no response) using publicly available contact information. Participants received a $10 incentive. Results: Responses were received from 66 of 95 institutions (69%), representing all 12 ACOG districts. An institutional protocol for postpartum Mg was reported by 70% (N=46) of respondents. Overall, 68% (N=45) would give a second course of Mg for an exacerbation of PESF, with no geographic variation (P=0.969). Most would administer a second course of Mg if the patient had a headache (N=52, 79%) or blood pressure ≥180/120 (N=35, 53%). The decision for a second course of Mg was not influenced by worsening laboratory values, gestational age at delivery, latency from delivery, or maternal demographics. Conclusions: Although there are no standardized guidelines for seizure prophylaxis in postpartum exacerbations of PESF, this national survey suggests that most academic programs favor giving a second course of Mg, especially in patients with headache or severe BP. A randomized trial comparing outcomes in patients who did or did not receive an additional course of Mg is warranted.

The authors have declared no competing interest.

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