Preeclampsia
New-onset hypertension after 20 weeks of gestation with proteinuria or end-organ dysfunction, driven by abnormal placental spiral artery remodeling and widespread endothelial dysfunction. Eclampsia is preeclampsia complicated by seizures; magnesium sulfate treats and prevents seizures, and prompt delivery is the only definitive cure for both.
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What this article covers
- Overview
A hypertensive disorder unique to pregnancy: new-onset hypertension after 20 weeks of gestation with proteinuria and/or new end-organ dysfunction, from abnormal remodeling of the placental spiral arteries.
- Epidemiology
Gestational hypertension progresses to preeclampsia in approximately one third of cases.
- Risk factors
History of preeclampsia in a prior pregnancy, the strongest single predictor.
- Pathophysiology
Abnormal placental spiral artery remodeling is the initiating event: cytotrophoblast invasion of the maternal spiral arteries fails to convert them into the low-resistance, high-capacitance vessels normal placentation requires.
- Clinical features
New hypertension after 20 weeks of gestation (systolic BP ≥140 mmHg or diastolic BP ≥90 mmHg, confirmed on two occasions ≥4 hours apart) is the anchor finding; it may be asymptomatic and detected only on routine prenatal screening.
- Differential diagnosis
HELLP syndrome: an overlapping extreme of severe preeclampsia; distinguished by microangiopathic hemolysis (schistocytes, elevated LDH), transaminases at least twice normal, and platelets…
- Diagnosis
Preeclampsia is established by new hypertension after 20 weeks (systolic BP ≥140 mmHg or diastolic BP ≥90 mmHg, two occasions ≥4 hours apart) plus proteinuria (≥300 mg/24h urine, protein:creatinine…
- Management
First, grade severity and gestational age; these two variables set the plan.
- Complications
Eclampsia (maternal seizures), with mortality driven by stroke, intracranial hemorrhage, and ARDS.
- Prognosis
Maternal risk diminishes rapidly within hours of delivery, though proteinuria may take weeks to months to resolve.
- Prevention
Start aspirin 81 mg PO once daily from 12 weeks of gestation through delivery in women at high risk (prior preeclampsia, multifetal gestation, chronic hypertension, pregestational diabetes, chronic…
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Related articles
- HELLP syndrome
HELLP syndrome is a thrombotic microangiopathy of pregnancy, a severe-feature variant of preeclampsia defined by hemolysis, transaminases at least twice the upper limit of normal, and a platelet count under 100,000/uL. Delivery is the only curative treatment; management pairs blood pressure control and magnesium sulfate seizure prophylaxis with prompt, gestational-age-guided delivery.
- Gestational hypertension
Gestational hypertension is new hypertension after 20 weeks of pregnancy without proteinuria or other features of preeclampsia. It requires close surveillance because a substantial proportion progresses to preeclampsia; management is blood pressure control with pregnancy-safe agents and timely delivery near term.
- Chronic hypertension in pregnancy
Chronic hypertension in pregnancy is hypertension predating pregnancy or diagnosed before 20 weeks. It raises the risk of superimposed preeclampsia, growth restriction, and abruption, so management is blood pressure control with pregnancy-safe agents, low-dose aspirin prophylaxis, close surveillance, and switching off teratogenic drugs preconception.
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