Pritchard’s Regimen: The Effect of 12-Hour Versus 24-Hour Magnesium Sulphate Maintenance Regimen on the Occurrence of Seizures and Maternal Outcome in Women with Severe Features of Preeclampsia: A Triple-Blind Randomized Controlled Trial

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Samuel Okuchukwu Ilikannu
Peter Ndidi Ebeigbe
Angela Uduak Ochei


Efficacy, Magnesium Sulphate, Preeclampsia with Severe Features, Randomized Controlled Trial, Seizures, Therapeutic Index


Background: Magnesium sulphate (MgSO4) administered for twenty-four hours is the drug of choice for seizure prophylaxis in patients with preeclampsia with severe features. Due to its narrow therapeutic index, a reduction in the duration of MgSO4 administered in the postpartum period may not only prevent the occurrence of seizures but also reduce the adverse effects associated with this drug.This study aim was to compare the efficacy of the 12-hour and 24-hour Pritchard’s MgSO4 maintenance regimen on the occurrence of seizures and maternal outcomes in patients with preeclampsia with severe features.

Methodology: A triple-blind randomized controlled trial was conducted among women with preeclampsia with severe features between 1st June 2022 and January 31st, 2023. The primary outcome measure was the occurrence of seizure in either arm of the study. One hundred and forty-six women were randomized into two groups, those who received a 12-hour MgSO4 regimen and placebo for the remaining twelve hours (Group I) and those who received a 24-hour MgSO4 regimen in the postpartum period (Group II). The collected data was coded and analyzed using Statistical Product and Service Solutions (SPSS) version 26 and p<0.05 was considered significant.

Results: There was no statistically significant difference between the two groups concerning the occurrence of seizures, the need to recommence MgSO4, clinical evidence of toxicity and adverse effects of MgSO4. There was also no statistically significant difference between the two groups in the total dose of MgSO4 administered, duration of urethral catheterization and duration of hospital admission. No maternal mortality was recorded in this study.

Conclusion: The results of this study suggest that the 12-hour MgSO4 maintenance regimen is as efficacious as the traditional 24-hour regimen in preventing seizures without worsening maternal outcomes.

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