Preeclampsia occurs in 3-14% of pregnancies and is defined by maternal hypertension with proteinurea, generally associated with edema, coagulation abnormalities, and disseminated intravascular coagulation. The conditions can lead to eclampsia, characterized by hyperreflexia and convulsions. Several organs are afflicted by the condition, most importantly the liver and kidneys. The direct cause of preeclampsia is unknown, but the initial events are linked to abnormalities of placentation. This implies abnormalities in trophoblast invasion and in physiological alterations of placental vessels required for adequate perfusion of the placenta, which leads to ischemia. The mechanisms that link the ischemic placenta to endothelial lesions and to stimulation of vasoconstrictors and inhibition of vasodilators are still subject of speculation. The only treatment of preeclampsia is delivery. Lowering of blood pressure and prevention of eclampsia with magnesium sulfate is indicated in severe preeclampsia. Despite numerous studies attempting to elucidate the exact etiopathogenesis of this complex multifactorial disease, prediction or prevention methods of preeclampsia are not available.