Right now, prematurity affects 9 percent of US births, and preterm birth and its complications are the leading cause of death in children under age 5 worldwide. "To date, no test on the market can reliably predict which pregnant moms will go on to preterm labor", comments Stacey D. Stewart, president of March of Dimes.
The small but significant studies, published in the journal Science on Thursday, were led by Stanford's Stephen Quake, who invented the first noninvasive prenatal blood test for Down syndrome and whose daughter was born nearly a month premature.
The test measures the activity of genetic material, called RNA, coming from the foetus, placenta and mother that ends up in the blood steam.
It has been found that certain genes give "signals" from which the risk of premature birth can be calculated even two months earlier than expected. This is the first truly significant scientific advancement in the problem of anticipation of premature labor that has been around for a long time, "said Danish researcher Mans Mellay".
Largest cause of infant mortality in U.S. Almost 9% of the babies in the United States are born premature which is the major reason for the death of children before the age of five across the globe.
Quake first became interested in this problem when he became a parent: his daughter was born almost a month premature. In contrast, the researchers anticipate that the new blood test will be simple and cheap enough to use in low-resource settings.
That highlights the "big question", Moley said: If this blood test - or any other test - becomes available, what can be done to prevent a woman from going into preterm labor? The scientists used blood samples from 21 of them to build a statistical model, which identified nine cell-free RNAs produced by the placenta that predict gestational age, and validated the model using samples from the remaining 10 women. While it's not exact, with accuracy at 45-percent, it's still close to the current benchmark method of ultrasound, which is 48-percent accurate. "The model's two most important features, CGA and CGB, encoding chorionic gonadotropin α and β3 subunits of human chorionic gonadotropin (HCG), are known contributors to pregnancy initiation", the authors point out.
In a study of 38 women at risk of preterm delivery, RNA markers were also identified.
The blood test can predict with 80% accuracy whether a woman will give birth prematurely.
"RNA corresponding to placental genes may provide an accurate estimate of fetal development and gestational age throughout pregnancy", the report found.
Work by the Stanford-led team had previously shown that the progress of pregnancy could be followed by measuring cfRNA from fetal tissues in maternal blood. A study by the University of Pennsylvania linked such births to changes in the mother's bacteria.
Quake, Tibshirani, Shaw and Stevenson are members of Stanford Bio-X; Tibshirani, Shaw and Stevenson are members of the Stanford Child Health Research Institute; Quake and Tibshirani are members of the Stanford Cancer Institute; Stevenson is an affiliate of the Stanford Woods Institute for the Environment; and Quake is a member of the Stanford Cardiovascular Institute, Stanford ChHEM-H and the Stanford Neurosciences Institute.
The Chan Zuckerberg Biohub has submitted a patent application for the new technology.