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Preeclampsia: Pathogenesis

Authors
S Ananth Karumanchi, MD
Kee-Hak Lim, MD
Phyllis August, MD, MPH
Section Editor
Susan M Ramin, MD
Deputy Editor
Vanessa A Barss, MD, FACOG

INTRODUCTION

Preeclampsia is a syndrome characterized by the onset of hypertension and either proteinuria or end-organ dysfunction after 20 weeks of gestation (table 1). Additional signs and symptoms that can occur include visual disturbances, headache, epigastric pain, thrombocytopenia, and abnormal liver function. These clinical manifestations result from mild to severe microangiopathy of target organs, including the brain, liver, kidney, and placenta [1]. Potential maternal sequelae include pulmonary edema, cerebral hemorrhage, hepatic failure, renal failure, and death. The fetal/neonatal burden of disease results from placental hypoperfusion and the frequent need for preterm delivery.

The pathophysiology of preeclampsia likely involves both maternal and fetal/placental factors. Abnormalities in the development of placental vasculature early in pregnancy may result in relative placental underperfusion/hypoxia/ischemia, which then leads to release of antiangiogenic factors into the maternal circulation that alter maternal systemic endothelial function and cause hypertension and other manifestations of the disease. However, the molecular basis for abnormal placental development and placental dysregulation of these pathogenic factors remains unknown. The role of angiogenic proteins in early placental vascular development are under investigation.

Our current understanding of mechanisms causing the pathologic changes observed in preeclampsia will be reviewed here. The clinical features and management of preeclampsia, and treatment of hypertension during pregnancy are discussed separately. (See "Preeclampsia: Clinical features and diagnosis" and "Preeclampsia: Management and prognosis" and "Management of hypertension in pregnant and postpartum women".)

ABNORMAL DEVELOPMENT OF THE PLACENTA

The critical role of the placenta in the pathophysiology of preeclampsia is supported by epidemiologic and experimental data that show:

Placental tissue is necessary for development of the disease, but the fetus is not [2-4]

              

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Literature review current through: Nov 2016. | This topic last updated: Wed Mar 09 00:00:00 GMT+00:00 2016.
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