Blood Test Predicts Preeclampsia Risk in Pregnant Women

The diagnosis of preeclampsia by using blood pressure and proteinuria is of limited use because they are tertiary, downstream features of the disease.

Placental growth factor (PlGF) is an angiogenic factor, a secondary marker of associated placental dysfunction in preeclampsia, with known low plasma concentrations in the disease.

In a prospective multicenter study, scientists at King’s College London (UK) studied the diagnostic accuracy of low plasma PlGF concentration in women presenting with suspected preeclampsia between 20 and 35 weeks’ gestation and up to 41 weeks’ gestation as a secondary analysis. Between January 2011 and February 2012, 649 women were recruited.

Plasma samples were tested, using the Triage PlGF Test (Alere; San Diego, CA, USA), at each study center. The assay uses fluorescently labeled recombinant murine monoclonal antibodies and detects PlGF specifically and quantitatively, in the range of 12 to 3,000 pg/mL, in about 15 minutes. In a normal pregnancy, the PIGF levels range from about 100 to 3,000 pg/mL and do not decrease during pregnancy.

The investigators said they could accurately predict the mother would develop preeclampsia if the protein levels were below 100 pg/mL. They also found that if a woman's PlGF levels fell below that threshold before her 35th week of pregnancy, her baby was likely to be delivered within two weeks, and about 61% developed preeclampsia.

Lucy C. Chappell, PhD, the senior author of the study said, “The test is designed to differentiate women with preeclampsia from those with high blood pressure alone. Current tests for the condition only detect that it's happening, rather than predicting it, and by that time the disease has progressed and has likely already caused organ damage. If you have very low levels of this protein called placental growth factor, it reflects the fact that your placenta is not growing well, and that is at the heart of the disease.” The study was published in the November 4, 2013, in the journal Circulation.

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King’s College London
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