FDA clears first blood test to diagnose preeclampsia

The FDA cleared a blood test in May that can detect a pregnant patient’s risk of developing preeclampsia, a potentially life-threatening high blood pressure condition.

The blood test, made by Thermo Fisher Scientific, is the first test for diagnosing preeclampsia to receive FDA clearance. In the “largest prospective US study to date” on predicting preeclampsia rates in diverse populations, which was published last year, the Thermo Fisher blood test determined with 96% accuracy which patients would not develop preeclampsia in the next two weeks and were therefore eligible for discharge.

“Patients and providers will benefit from having better tests to predict progression to preeclampsia with severe features, especially for those patients at risk of severe, early-onset disease or for whom there is some diagnostic uncertainty,” Preeclampsia Foundation CEO Eleni Tsigas said in a statement.

Preeclampsia occurs in approximately one in 25 pregnancies in the US, and Black pregnant patients are 60% more likely to develop the condition compared to their white counterparts, according to the CDC. Worldwide, the condition leads to 70,000 maternal deaths and 500,000 fetal deaths each year.

The blood tests analyze the ratio of two proteins produced by the placenta, and pregnant patients who had a ratio above 40 had a 65% likelihood of developing severe preeclampsia in the next two weeks, according to the study, which tracked more than 1,000 pregnant patients hospitalized with a hypertensive pregnancy disorder at 18 US medical centers between 2019 and 2021.

Prior to the development of the blood test, hospitals couldn’t accurately predict the onset of preeclampsia early in pregnancy, and treated pregnant patients only after a diagnosis, which is both “insufficient and costly,” according to the CDC. In the US, preeclampsia was responsible for about 6% of all maternal deaths in recent years, according to PBS NewsHour.

In 2012, treating preeclampsia cost the US healthcare system more than $2 billion in the first 12 months after delivery, according to a 2017 study analyzing the economic burden of the condition. Patients with preeclampsia accrued an average of $41,790 in both maternal and infant medical costs, compared to $13,187 for patients without complications, a 2019 study looking at electronic health record and billing data from births between 2010 and 2015 at Pennsylvania-based Geisinger Health System.

The tests, which have limited availability, are expected to become more widely accessible in the coming months, PBS NewsHour reported earlier this month.