Increased bleeding time after magnesium sulfate infusion

Personal observation suggested that blood loss increased among patients with preeclampsia who received magnesium sulfate infusions. Bleeding time (modified Ivy) was checked before infusion of magnesium and at the completion of infusion for nine patients with preeclampsia and three who did not receive magnesium. Bleeding time more than doubled among patients who needed magnesium and did not change among controls.