New blood test may detect whether pregnant women will be affected by preeclampsia

A new blood test can detect whether pregnant women will be affected by preeclampsia, which can cause stroke, organ damage and premature birth months before symptoms appear.


Preeclampsia is a blood pressure disorder that occurs in about one in 20 pregnancies, usually in the third trimester. Hypertensive disorders related to pregnancy are one of the leading causes of maternal death globally.

The experimental new test, created by Mirvi, a company based in South San Francisco, analyzes chemical messages, a type of RNA, from the mother, baby and placenta to help doctors look at preeclampsia indicators at potentially 16 to 18 weeks into pregnancy. make capable. That time frame is before the symptoms of preeclampsia, such as swelling, protein in the urine, and high blood pressure, will begin to appear.


magazine on wednesday nature Published research showed that the test was able to correctly identify 75 percent of women who developed preeclampsia.

“It is often in the first trimester that the onset of the condition is biological,” said Manish Jain, CEO of Mirvi, “despite the symptoms appearing late in pregnancy.”


Detecting preeclampsia after you have symptoms, Jain said, “gives you very little time to address the challenge. And that’s mostly crisis management.”

While the blood test is still being done and will not be available for some time, advocates for doctors and parents say it could save lives.

An experimental new test, created by California-based Mirvi, analyzes chemical messages, a type of RNA, from a mother, baby and placenta, enabling doctors to find preeclampsia indicators potentially 16 to 18 weeks into pregnancy. In this photo, a pregnant woman holds her belly on September 27, 2016 in Cardiff, United Kingdom.
Matthew Horwood / Getty Images

Bekah Bischoff of Louisville, Kentucky, who developed preeclampsia during two pregnancies and now helps others who have the condition, said she was diagnosed late in the third trimester both times. While pregnant with her son, Henry, in 2012, she discovered that at 36 weeks she had a very serious type of HELLP syndrome. She was delivered that day. She almost died.


“Just think of all the chaos and the heartbreak and all the trauma, really, that went with it that could have been avoided if just a simple test could be done,” she said.

Diagnosis of preeclampsia now includes testing the urine for protein, measuring blood pressure, and performing other tests if suspected. Treatment may include bed rest, medication, hospital monitoring, or labor at the end of pregnancy.

Earlier studies have also suggested that circulating RNA may predict preeclampsia. but the author of nature The study looked at a large and diverse data set, analyzing RNA in 2,539 blood samples from 1,840 women in the Americas, Europe and Africa to see how a test might work. After the RNA messages were detected, a computer analyzed them for patterns. Although the test “strongly” predicted preeclampsia in those who got it, the study said, there were some people who predicted they would get the disorder than those who did not.


The study’s senior author, Dr. Thomas McElrath of Brigham and Women’s Hospital in Boston, hopes that the test can also be used for the early detection of other pregnancy complications, such as gestational diabetes. The scientists said Mirvi’s approach reveals the underlying biology of healthy pregnancies. And by understanding what those normal RNA “profiles” look like, researchers say they can find early signs of risks for other problems when these patterns differ in particular ways. He said more research is needed to determine how the test can detect these other conditions, and to further validate the results of preeclampsia.

Jain said it was too early to say when the test might be available to the public, but he may have a better idea of ​​the timing by the end of the year. McElrath is Mirvie’s scientific advisor and has a financial interest in the company, as do some of the other authors of the Nature paper. There are inventories on some patent applications that cover the detection or treatment of pregnancy complications. The study was paid for by Mirvi.

Cedars-Sinai in Los Angeles with Dr. S. Anantha Karumanchi, who has done extensive research on preeclampsia, but was not involved in nature Early detection of the condition would allow doctors to make simple adjustments, such as giving women low-dose aspirin, to delay the onset of preeclampsia, the study said.

“There is no question that there is a clear medical need,” Karumanchi said. Looking at the data in the paper, he said, the scientists’ method “appears to be superior to existing types of methods being used around the world.” If validated by other studies, “clearly something like this would need to be done.”

Bischoff, who now works for the Preeclampsia Foundation, agreed. When she was about five months old with her son, she said, she felt a lack of energy and was gaining more weight than she thought. But when she asked people on her medical team about these kinds of problems, she recalled, she was told that things were normal — like the many other women she’s met who have had preeclampsia.

A blood test, she said, “will clear the barrier of fighting to be heard.”

The Associated Press contributed to this report.