Air pollution could be to blame for millions of premature births occurring globally each year, scientists claim.  

Microscopic pollutants given off in diesel emissions and agricultural fires can become lodged in the lungs of expectant mothers.  

This then gets passed down to the developing child and leaves them at risk of being born early, experts warn. A report now suggests this could be the cause of more than 3.4million premature births across the world since 2010.  

Researchers for the Stockholm Environment Institute focused on fine particulate matter - small than 2.5 micrometres in diameter.  

They found that this form of pollution was most dangerous in sub-Saharan Africa, north Africa and south-east Asia.   

These three regions of the world make up for 60 per cent of all of the premature births worldwide, they said.  

SOUTH ASIA had the most air-pollution related preterm births at up to 1.6million incidences, the report showed.Although China has a relatively low rate of premature births, the report revealed that up to 521,000 cases could be linked to air pollution.  

Yet, a lack of research in these areas prompted separate researchers to describe this figure as ‘conservative’, The Guardian reports.  

Dr Paul Jarris, chief medical officer at the March of Dimes, a US-based organisation focused on maternal and baby health said: ‘Preterm birth and associated conditions are one of the biggest killers of children in the US and worldwide.  

‘Yet, there’s a lot of things we don’t know about what causes preterm birth, so every bit of information we can get is helpful.’We have known for a long time that air pollution contributes to asthma and heart disease in adults.  

‘What I think people fail to recognise is that so many of these risk factors impact babies before they are even born.’   

He added: ‘This is one more reason why we need to be good stewards of the environment.  
‘The most vulnerable among us – unborn children – are affected, and really in a way that impacts families’ lives for generations.’   

Nearly 15million babies worldwide are born each year before reaching 37 weeks gestation, figures suggest.  

Around one in 13 babies in the UK and one in 10 in the US are born prematurely.   

And according to the World Health Organisation, it is the leading cause of death in infants under the age of five.  

Premature babies are at an increased risk of health problems, particularly related to breathing, feeding and infections.  

In the long term, premature babies can suffer disabilities and impaired hearing and sight.  

POLLUTION RAISES RISK OF DEMENTIA   

Air pollution raises the risk of dementia by 92 per cent, researchers at the University of South California found.  

Toxic fumes from cars and power plants causes brains to swell, leading to dementia.  
This may cause a fifth of global cases.  

Women with the ‘dementia gene’ or living in heavily polluted areas are most at risk.