Washington, Sep 7 (PTI) Scientists have identified six gene areas that influence length of pregnancy, a finding that may lead to new ways to prevent preterm birth – the leading cause of death among children under age five worldwide.

The study involved data from more than 50,000 women.

The findings, published today in the New England Journal of Medicine, may help prevent preterm birth and its consequences.

Preterm birth is defined as any birth occurring before 37 weeks of pregnancy.

In addition to the risk of death, babies who survive an early birth often face serious, lifelong health problems, including chronic lung disease, vision and hearing impairment, cerebral palsy, and neurodevelopmental disabilities.

The scientific world has been hunting for the causes of preterm birth for decades.

“We have known for a long time that preterm birth is a combination of genetic and environmental factors. Previous research has suggested that about 30 to 40 per cent of the risk for preterm birth is linked to genetic factors,” said Louis Muglia from Cincinnati Children’s Hospital in the US.

“This new study is the first to provide robust information as to what some of those genetic factors actually are,” said Muglia.

The study assembled extensive genomic data from at least five times as many pregnant women than had been gathered by any previous study of pregnancy and preterm birth, Muglia said.

The findings are based heavily on data from more than 44,000 women who provided saliva samples. These women also answered questions about their past pregnancies and agreed that their genetic information could be analyzed, anonymously.

The six gene areas identified by the project serve as a launching platform for deeper research, some of which has already begun.

Potential diagnostic tests, new medications, improved dietary supplements or other changes that could help more women have full-term pregnancies will require several more years of study, researchers said.

One of the gene areas identified suggests that cells within the lining of the uterus play a larger-than-expected role in the length of pregnancy, which in turn provides a new target for medications to help prevent preterm birth.

Another newly identified gene area raises important questions about how a lack of selenium – a common dietary mineral found in some nuts, certain green vegetables, liver and other meats – might affect preterm birth risk.

People living in regions with low selenium in soil and diet, and people who live in low-income “food deserts” are most at risk of having a lack of selenium in their diets.

This is published unedited from the PTI feed.