Children born before 37 weeks face a much higher risk of dying before age five. Predicting preterm birth (PTB) is difficult because of varied causes and lack of reliable tests. Now, scientists say blood cell-free RNA (cfRNA) can predict PTB over four months before delivery.
Dr. Wen-Jing Wang from BGI Research and Professor Chemming Xu from Fudan University studied 851 pregnancies. They analyzed blood samples taken around 16 weeks gestation, including 299 preterm and 552 full-term births. They found clear differences in cfRNA between preterm and full-term births.
Their study covered preterm births both with intact membranes and those with early water breakage. Less than 3% had a previous preterm birth. Dr. Wang says this early detection window shows biological changes happen months before current clinical signs.
Every year, about 13.4 million babies are born prematurely worldwide. Nearly one million of these infants die before age five. Preterm babies face many health risks due to immature organs, such as breathing issues, infections, and feeding problems.
Long-term effects include cerebral palsy, epilepsy, and blindness. Families also endure significant emotional and financial stress caring for these children. Early prediction could help improve prevention and care.
The new test uses the same blood sample timing as routine prenatal screening (NIPT), allowing combined testing. Current sequencing costs are similar to NIPT but could drop with targeted methods. This may enable wide population screening and better monitoring of high-risk pregnancies.
Unlike DNA or immune markers, cfRNA reflects dynamic and tissue-specific changes. The team identified infection and inflammation signals in cases with water breakage, and metabolism changes in intact membrane cases. These matched clinical observations.
Dr. Wang calls this a “liquid biopsy” that could revolutionize how pregnancy complications are understood and managed. However, RNA’s instability means standardized sample handling protocols are needed before broad use.
Researchers also aim to improve prediction algorithms across diverse populations and study causes of different PTB types. They seek collaborations to speed clinical application of their findings.
Professor Alexandre Reymond, chair of the conference, praised the work. He said new sequencing methods now enable risk evaluation through gene expression, not just genetics, opening fresh diagnostic possibilities.
