Air pollution may have contributed to almost 6million premature births and nearly 3million babies being born underweight around the world in 2019, a study claims.
And it wasn’t just pollution from traffic or power plants, which have commonly been thought to be the biggest source of toxic air.
Indoor cooking stoves contributed to around two thirds of the cases, according to the research by the University of California in San Francisco.
Researchers analysed how outdoor and indoor air pollution impacted pregnancy outcomes around the world.
They found the global number of preterm births and underweight babies could be cut by 78 per cent if air pollution was minimised in Southeast Asia and sub-Saharan Africa.
The authors said indoor pollution, from burning coal, dung, and wood inside homes, is common in these regions with preterm births rates also the highest in the world.
But air pollution, and its subsequent impact on pregnancies, is not only a problem in the developing world.
The study also found that outdoor air pollution contributed to an estimated 12,000 preterm births in the US in 2019. An estimate wasn’t given for the UK.
A growing number of studies have pointed to pollution as a factor leading to premature births and miscarriages. Previous research has suggested this is partly a result of women suffering inflammation and ‘internal stress’ from pollutants.
New research has show a combination of outdoor and indoor air pollution was a likely contributor to almost 6 million premature births and nearly 3 million babies being born underweight around the world in 2019. The study authors say the findings should prompt nations to tackle the problem to save the lives of new born children
The researchers do not detail how many of the 6million babies born prematurely as a result of air pollution in 2019 survived.
However, they do note that preterm birth is leading cause of newborn mortality worldwide.
The World Health Organization estimates that 1million babies die every year due to preterm birth complications.
Children born prematurely, as well as all babies born with a low birth weight, are at increased risk of developing major illness throughout their lives.
These can range from respiratory illnesses, bleeding in the brain and problems with heart and digestive system, and long term intellectual and developmental disabilities.
Professor Rakesh Ghosh, the study’s main author, said the global health impact of air pollution was immense.
‘The air pollution-attributable burden is enormous, yet with sufficient effort, it could be largely mitigated,’ he said.
Professor Ghosh said the findings should be a wake up call for nations to tackle air pollution for the sake of the next generation.
‘With this new, global and more rigorously generated evidence, air pollution should now be considered a major driver of infant morbidity and mortality, not just of chronic adult diseases,’ he said.
‘Our study suggests that taking measures to mitigate climate change and reduce air pollution levels will have significant health co-benefit for newborns.’
The findings were published in the journal PLOS Medicine.
Premature birth charity, Bliss, estimates that 60,000 babies are born prematurely in the UK every year, accounting for one out of every thirteen births.
In the US, there are about 380,000 premature births a year, accounting for one in ten births according to pregnancy health campaign group March of Dimes.
This latest study is the latest in a series of research linking air pollution and problems in pregnancy.
Women exposed to air pollution before getting pregnant are nearly 20 per cent more likely to have babies with birth defects, research suggested in January 2018.
Living within 3.1 miles (5km) of a highly-polluted area one month before conceiving makes women more likely to give birth to babies with defects such as cleft palates or lips, a study by University of Cincinnati found.
For every 0.01mg/m3 increase in fine air particles, birth defects rise by 19 per cent, the research adds.
Previous research suggests this causes birth defects as a result of women suffering inflammation and ‘internal stress’.