Promising new blood-test for preterm birth risk

14 February 2017
Premature baby

New Zealand researchers a the University of Auckland's Liggins Institute are working to develop a mid-pregnancy blood test to predict premature birth that could help millions of mothers and babies worldwide.

The research could revolutionise the care of pregnant women at risk of giving birth too early (before 37 weeks pregnancy).

About 60 percent of preterm births occur spontaneously, often in women with no prior history or warning. Currently, there is no way of reliably predicting whether an individual woman will go into labour prematurely.

This may be about to change.

The researchers have already identified a unique molecular fingerprint in blood taken from women at 20 weeks of pregnancy who all went on to have their babies early. The fingerprint was not present in blood taken from women at the same stage in pregnancy who went on to deliver at term.

The team are now following up that pilot study with a two-year study that will test a bigger pool of samples, including samples taken at 15 weeks as well as at 20 weeks, to check whether the fingerprint is a reliable biomarker for preterm birth.

“This is exciting, as it could potentially lead to much better outcomes for the babies and their mothers, in the short and long terms, says study co-lead and Liggins Institute Professor Mark Vickers. “It could enable the targeting of existing and future therapies to delay or even prevent preterm birth.”

The potential biomarker revealed in the pilot study was derived from micro-RNA (miRNA) analysis. MiRNAs are small non-coding RNA molecules that play key roles in the regulation of gene expression. MiRNAs are also known to be involved in the development of and protection from a range of diseases. Recent studies in this fast-emerging field have highlighted the potential for miRNAs as biomarkers for osteoporosis, cancer and the pregnancy complication pre-eclampsia.

The Auckland researchers used state-of-the-art digital technology called NanoString that is much more sensitive and faster than other available methods.

Globally, more than one in 10 babies are born too early. In New Zealand, around 5000 babies are born prematurely every year – that’s about one in 13 of all live births, and one in seven for Maori. If born earlier than 24 weeks the large majority of these children die. While the majority born after 24 weeks survive the health care costs can be huge. These children carry a greater risk of problems with learning and development, cerebral palsy, growth, and later adult diseases such as obesity and diabetes.

“If we can develop a reliable blood test to identify women who will have a spontaneous preterm birth by mid pregnancy this has potential to lead to a huge advance in clinical practice,” says study co-lead, Professor Lesley McCowan from the Obstetrics and Gynaecology Department at the University of Auckland Medical School.

“Women at high risk could then receive tailored care that may reduce the risk of early birth and optimise the health of those babies who are born early.”