Spending time in the sun in early pregnancy could help women reduce the risk of giving birth prematurely, a new study suggests.

Researchers found that women who get more sunlight in their first trimester lessen the chances of developing problems with their placenta associated with preterm birth and losing a baby.

The research team found that the likelihood of those exposed to the lowest available sunlight giving birth prematurely was 10% higher than women experiencing the highest levels.

Experts at the University of Edinburgh analysed maternity care data for 397,370 mothers and 556,376 babies born after 24 weeks of pregnancy.

Maternity records of all single live births in Scotland between 2000 and 2010 were then cross-checked with postcode-specific weather records from the same period.

Dr Sarah Stock, of the University of Edinburgh’s Usher Institute, said: “The role of sunlight is an exciting new avenue for research into preterm birth prevention.

“This study is important because it provides further data reminding us that sunlight has health benefits as well as risks.”

Sun exposure in the second trimester was not shown to have any impact on premature birth risk.

Researchers say their findings – which were independent of other risk factors such as age and smoking – could help shape the advice given to families during pregnancy.

The team says more work is needed to better understand the link between sunshine and premature birth.

Researchers from the University of Edinburgh had previously shown that when our skin is exposed to the sun’s rays, a compound – called nitric oxide – is released to our blood vessels that helps lower blood pressure.

This previous work suggested that exposure to sunlight improves health overall, because the benefits of reducing blood pressure far outweigh the risk of developing skin cancer.

Sunlight also directly contributes to vitamin D production, which helps with the development of an unborn baby’s bones, teeth, kidneys, heart and nervous system.

Complications caused by preterm birth – defined as babies born alive before 37 weeks of pregnancy – are the leading cause of death in children under five years old.

Survivors of preterm birth have higher rates of disability, including learning disabilities and visual and hearing problems, than those born at term.

The team hopes further research can help develop ways to reduce preterm birth and subsequent childhood morbidity and mortality.

This research was funded by Tommy’s and is published in the scientific journal Frontiers.