Air pollution linked to women in cities giving birth to smaller babies - scientists call for more green spaces

Women who live in cities and are therefore exposed to more air pollution tend to give birth to smaller babies than women living in the countryside, new research has suggested.

Scientists looked at 4,286 children living in five countries across Europe - Denmark, Estonia, Iceland, Norway and Sweden - and measured the levels of air pollution in the areas where their mothers lived while pregnant.

Results showed that women living in places with a higher concentration of pollutants known as PM2.5, which are released by traffic fumes and emissions, gave birth to babies that were 56g lighter than those in areas of with a lower concentration of pollutants. Meanwhile, women who lived in the countryside, or in areas with green spaces such as parks or fields, had babies with slightly higher birth weights - 27g heavier on average.

It follows research in the past which has shown that air pollution can impair normal foetal development, increasing the risks of miscarriage, premature births, and low birth weight. Scientists have also previously found a relationship between birthweight and lung health, with children who are lighter when they are first born facing a higher risk of asthma an chronic obstructive pulmonary diseases (COPD).

The lead author of the study, Robin Mzati Sinsamala from the University of Bergen in Norway, explained: “The time when babies are growing in the womb is critical for lung development. We know that babies with a lower birth weight are susceptible to chest infections, and that this can lead to problems such as asthma and COPD later on.”

On why living in areas with higher levels of “greeness” can help combat this effect, Mr Sinsamala added: “It could be that green areas have lower traffic [and so less emissions], or that plants help to clear the air of pollution, or green areas may mean it’s easier for pregnant women to be physically active.”

The new research, which will be presented at the European Respiratory Society International Congress in Milan, Italy, is part of a wider program of research called Life-GAP that is investigating the effects of air pollution and ‘greenness’ on lung health in generations of Europeans.

Professor Arzu Yorgancioglu, from the European Respiratory Society, commented: “This study adds to a growing body of evidence on the damage that air pollution is having on our health, especially in vulnerable babies and young children. Women who are pregnant will want to protect their babies from potential harm.”

However, Professor Yorgancioglu pointed out how difficult it can be for individuals to reduce their exposure to pollution, or make their homes and neighbourhoods ‘greener’. “[So], as doctors and researchers who care about children’s health, we need to put pressure on governments and policymakers to lower the levels of pollution in the air we breathe,” she said.

This can include simply adding more parks or green spaces to cities and urban areas, she explained, given the fact that not everyone can just move away to the countryside.

Dr Meenakshi Choudhary, a senior consultant in reproductive medicine at Newcastle upon Tyne Hospitals NHS Foundation Trust, also called for “urgent action from global policymakers and governments” as a result of the study, calling on them to “address air pollution and its health consequences.”

However, she also sought to reassure potentially anxious mothers, remarking: “It’s essential to approach these findings with measured consideration, as the observed difference in birth weight, while notable, was relatively small.”

The study comes at a time when pollution has been a focal point in politics, particularly in the UK, with capital city London facing controversy over Mayor Sadiq Khan’s Ultra Low Emission Zone (ULEZ). The scheme was recently expanded to include Greater London, prompting critics to lash out over the £12.50 per day charge that will be imposed on any vehicle entering the zone which doesn’t meet its emission standards.

However, Khan has stood firm on ULEZ - insisting both that most cars and vehicles meet the requirements, and that the change is good for Londoners. He previously told NationalWorld: “The reality is that air pollution is a matter of life and death. I believe breathing clean air should be a human right rather than a privilege. London’s policies are world-leading in this regard.”

Research shows that between 29,000 to 43,000 people in the UK die each year because of air pollution. According to the World Health Organisation, the combined effects of ambient air pollution and household air pollution are associated with 6.7 million premature deaths worldwide each year.