Hypertensive disorders of pregnancy are one of the leading causes of maternal morbidity and mortality worldwide. The majority of clinical research has focused on pregnancy-related hypertension that develops in the antenatal period, while studies of the incidence, risk factors, and prevention of postpartum hypertension are limited. In particular, there is a paucity of data about the clinical entity known as de novo postpartum hypertension, in which women who are normotensive throughout pregnancy and delivery subsequently go on to develop high blood pressure in the immediate to late postpartum period. Of those with postpartum preeclampsia, 33-69% were normotensive antepartum.~Early identification and treatment of antepartum preeclampsia has been shown to decrease some severe maternal outcomes. Conversely, women with de novo postpartum hypertensive disorders remain among the highest risk for severe maternal morbidity due to decreased surveillance and lack of data regarding preventive therapies and interventions. Evidence from multiple randomized controlled trials have demonstrated a benefit in the use of oral loop-diuretics in decreasing postpartum systolic blood pressure, promoting faster normalization of blood pressure, and decreasing the need for antihypertensive therapy in women with an antenatal diagnosis of preeclampsia. Biological plausibility suggests that loop-diuretic therapy may similarly mitigate the normal physiologic mechanism that has been implicated in the pathogenesis of hypertensive complications after delivery in women at risk for de novo postpartum hypertension.~This study is a double-blind randomized placebo-controlled trial of 82 high-risk women to assess whether treatment with oral Lasix (furosemide) after delivery reduces blood pressure at the time of discharge. Women at high risk for de novo postpartum hypertension will be randomized to a five-day course of either 20 mg oral Lasix (furosemide) or placebo once daily initiated after delivery. Women will be monitored through their routine 2-week and 6-week postpartum visits, during which times hypertensive complications and adverse effects of therapy will be assessed.
Primary objective: To evaluate whether oral furosemide can help prevent de novo postpartum hypertension (new-onset high blood pressure after delivery) by reducing blood pressure after delivery in high-risk women.~Secondary objectives: To evaluate whether oral furosemide administered to high-risk women after delivery can reduce the frequency of postpartum hypertensive episodes, the need for antihypertensive therapy, the risk of postpartum preeclampsia, and the incidence of severe maternal morbidity.