New risk prediction model developed for premature births

Researchers hope treatment can be better-targeted and allow pregnant women to spend less unnecessary time in hospital

More and more babies are being born prematurely, according to the WHO (Getty Images)

A newly-developed tool could help protect babies and reduce women’s time in hospital by improving the prediction of premature births.

A premature birth is defined by the World Health Organisation (WHO) as “being born alive before 37 weeks of pregnancy are completed.” An estimated 15 million babies are born pre-term each year, with related complications being the number one cause of death among children under five years of age.

The health of pre-term babies can be significantly improved by timely interventions.

However, pre-term labour is particularly hard to diagnose which can lead to unnecessary overtreatment as well as stress and disruption for the expecting mother.

Researchers at the University of Edinburgh found that very few admissions to hospital, where women displayed signs and symptoms of preterm birth, actually resulted in the women going on to give birth in the next few days or week.

A visit to hospital in the final stages of pregnancy can be very disruptive for mothers, researcher and consultant obstetrician Dr Sarah Stock fromtold The Independent.

She added that some women will have to go “a long way from home” to get to a hospital with appropriate facilities for treatment and that drugs could have unpleasant side effects.

In creating a preterm birth risk prediction model, Dr Stock said she hopes treatment can be targeted and allow pregnant women better information to make their own decisions, based on how likely the women are to deliver their baby prematurely.

To develop the model, Dr Stock and University of Edinburgh colleagues used published data taken from five European prospective cohort studies, including 1,783 pregnant European women. This information was then used to create a model to predict the risk of spontaneous pre-term birth.

Researchers validated the model in a study of 2,924 women who were displaying signs and symptoms of preterm labour from 26 consultant-led obstetric units in the UK. This demonstrated the difference between their predicted and the observed outcomes.

Factors taken into account when using the tool include the age of the women, whether or not they have given birth before, whether they are expecting twins, their ethnicity and whether or not they smoke. These, together with the results of a specific protein concentration analysis (taken by a swab taken using a speculum), can indicate the likelihood that the woman will give birth within the next seven days, according to Dr Stock.

If the mother is at high risk of birth within the next week then they can be treated accordingly, or if not they can be reassured and allowed to make informed decisions on treatment options.

Further studies would therefore be needed to determine whether the risk prediction model improves clinical outcomes in practice. Dr Stock hopes however that with more widespread use of the tool, for example linking the predictor to maternity records, some of the limitations of the study could be addressed.

Jane Brewin, chief executive of Tommy’s charity which funded the study, said: “Most mothers with signs of premature labour are still pregnant a week later, and this study shows the typical NHS tests aren’t accurate enough to tell who’s really at risk, which can put undue strain on expectant parents and on the NHS.

“Our latest research clearly demonstrates that fetal fibronectin testing can reduce the economic and emotional toll of this issue, being more cost-effective while reassuring families who may otherwise be very anxious about the risk of premature birth and helping to make pregnancy safer for those who do need special care.

“With 60,000 babies born prematurely each year in the UK, there’s an urgent need for better ways to predict and manage that risk.

“Fetal fibronectin tests are used in our specialist clinics already, but everyone should be able to benefit from this pioneering and potentially lifesaving tool; we urge the government to include these tests as standard in national maternity care guidelines, so that precious NHS resources can be focused on those most in need.”

The study has been published in the PLOS Medicine journal.