There is no definitive cause of preeclampsia, though it is likely related to a number of factors. Some of these factors include: 

Those with long term high blood pressure have a risk 7 to 8 times higher than those without.

Physiologically, research has linked preeclampsia to the following physiologic changes: alterations in the interaction between the maternal immune response and the placenta, placental injury, endothelial cell injury, altered vascular reactivity, oxidative stress, imbalance among vasoactive substances, decreased intravascular volume, and disseminated intravascular coagulation.

While the exact cause of preeclampsia remains unclear, there is strong evidence that a major cause predisposing a susceptible woman to preeclampsia is an abnormally implanted placenta. This abnormally implanted placenta is thought to result in poor uterine and placental perfusion, yielding a state of hypoxia and increased oxidative stress and the release of anti-angiogenic proteins into the maternal plasma along with inflammatory mediators. A major consequence of all this is generalized endothelial dysfunction. The abnormal implantation is thought to stem from the maternal immune system's response to the placenta and refers to evidence suggesting a lack of established immunological tolerance in pregnancy. Endothelial dysfunction results in hypertension and many of the other symptoms and complications associated with preclampsia.

Causes
Diagnosis
Risk factors
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