A blood test commonly used to detect fetal genetic abnormalities can be modified to help predict complications associated with pregnancy before any symptoms develop, according to UCLA researchers and colleagues.

Their preliminary study is the first to link certain cell-free nucleic acids—genetic material shed from the placenta into the mother’s blood—to adverse outcomes in pregnancy, including ischemic placental disease and gestational diabetes, and to show that analyzing blood for such cell-free DNA signatures could potentially predict these serious complications.

The researchers found that during the first and early second trimesters, placenta-specific DNA increased among those women who went on to develop gestational diabetes. They also identified several differently expressed genes and created a model with a predictive value for adverse pregnancy outcomes.

Background

Although the analysis of genetic material in mothers’ blood has been used to screen for genetic abnormalities in pregnancy, this is the first time these specific methods of screening for cell-free DNA signatures have been used as a means of providing a more accurate prediction.

The research points to a promising approach that could improve outcomes for mothers and their babies using existing technologies, says the study’s lead author, Sherin Devaskar, MD, physician-in-chief of UCLA Mattel Children’s Hospital and a distinguished professor of pediatrics at the David Geffen School of Medicine at UCLA.

Method

The study followed a diverse group of pregnant women between February 2017 and January 2019, testing their blood periodically throughout gestation. By the end of the study, 160 participants had given birth, with 102 maternal and 25 cord plasma samples taken along the way.

Impact

If confirmed in larger studies, cell-free DNA blood tests may help identify issues in the placenta as an indicator of a healthy mother and fetus.

“The novelty of this research is being able to break down a mother’s DNA and being able to hone in on the health of the placenta—something that researchers have never been able to do before,” Devaskar says. “This research warrants application of automated methodologies in multicenter trials to improve future testing and screening for all women.”

Funding was provided by the National Institute of Child Health and Human Development, a program of the National Institutes of Health, as part of the Human Placenta Project.

Reference

Del Vecchio G, Li Q, Li W, et al. Cell-free DNA Methylation and Transcriptomic Signature Prediction of Pregnancies with Adverse Outcomes [published online ahead of print, 2020 Oct 13]. Epigenetics. 2020;1-20. doi:10.1080/15592294.2020.1816774