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Preeclampsia - Cause

Experts don't know the exact cause of preeclampsia.

But it may start with a poorly developed placenta that doesn't circulate blood normally. What causes this placenta problem isn't yet clear. Experts also don't know why the mother's body then develops high blood pressure.

Immune system response

Preeclampsia occurs most often in women who are pregnant for the first time and in women who have been pregnant before but now have a first pregnancy with a different man.

Exposure to an antigen from the father (in the growing placenta or fetus, for example) may trigger an immune response in the woman's body. This immune response—the body's way of fighting infection—may result in narrowing of the blood vessels throughout the body, causing higher blood pressure and other problems.

    This information is produced and provided by the National Cancer Institute (NCI). The information in this topic may have changed since it was written. For the most current information, contact the National Cancer Institute via the Internet web site at http:// cancer .gov or call 1-800-4-CANCER.

    WebMD Medical Reference from Healthwise

    Last Updated: January 21, 2014
    This information is not intended to replace the advice of a doctor. Healthwise disclaims any liability for the decisions you make based on this information.
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