Air Pollution Linked to Nearly Half of all Stillbirths
Air pollution
The new study is the latest addition to an ever-growing mountain of evidence documenting the negative effects of air pollutants on human health.

In 2020, UNICEF estimated that “a stillbirth occurs every 16 seconds somewhere in the world.” A new study has linked air pollution to nearly half of them.

The study of 137 countries is the first global analysis to assess the number of fetal deaths, putting into numbers the already documented link between fine particulate matter (PM2.5) concentrations and stillbirths. PM2.5 is primarily produced through the burning of fossil fuels. 

The United Nations estimates around two million stillbirths occur every year, and describes the global burden of stillbirths as a ‘neglected tragedy’. Some 98% of stillbirths are estimated to occur in low- and middle-income countries across Asia, Africa, and Latin America. 

Progress in combatting the crisis has stalled, and stillbirths continue to receive little attention on the global health agenda. Despite their impacts on millions around the world, stillbirths are not included in the Millennium Development Goals targets. 

“Current efforts to prevent stillbirth focus on medical service improvements but compared to clinical risk factors, environmental ones are usually unseen.” Dr Tao Xue, the first author of the study, told the Guardian

“Clean air policies, which have been enacted in some countries, such as China, can prevent stillbirths. In addition, personal protections against air pollution, i.e. wearing masks, installing air purifiers, and avoiding going outside when air pollution occurs could also protect vulnerable pregnant women.” 

A neglected tragedy

Air pollution
The United Nations estimates 98% of all stillbirths occur in low-and middle-income countries.

The study estimates cutting air pollution to the World Health Organization’s recommended limits could prevent 710,000 stillbirths a year, but the exact mechanisms behind how air pollution causes stillbirths are still unclear. 

The researchers found PM2.5 particles could be passing from the mother to the foetus through the placenta, which may not only harm the placenta but also potentially cause “irreversible embryonic damage.” A 2018 study found toxic pollutant particles in the lungs, livers and brains of foetuses. Further, PM2.5 exposure during pregnancy could also reduce oxygen transfer to the foetus or cause placental abnormalities – all possible causes of stillbirths. 

The study also stressed that the impacts of stillbirths stretch far beyond the strictly medical. Stillbirths have well-documented links to psychological conditions like anxiety, grief, and post-traumatic stress disorders, and the economic burdens resulting from healthcare costs and the inability to work affect individuals and their families – often driving sex inequalities as a consequence.

Air pollution is a global epidemic

Air pollution
Mounting scientific evidence on the adverse health effects of air pollution shows cutting PM2.5 concentrations would save the lives of millions.

This latest study adds to a mounting pile of evidence on the harms of air pollution. It kills nearly seven million people every year, penetrates the brain and lungs of fetuses, is correlated with adverse birth outcomes like miscarriages, pre-mature birth and low birthweight, and is linked to adverse brain development in young children.

In 2021, the World Health Organization slashed its limit on air pollution concentration in half, urging nations to tackle polluted air to save millions of lives. WHO estimates 99% of the global population now breathes air beyond its recommended limit. Earlier this year, the Lancet found air pollution is the world’s largest environmental risk factor for disease and premature death.

While the exact number of stillbirths that could be prevented through meaningful reductions in air pollution is unknown, the study is the latest of a long series of scientific footnotes showing that slashing PM2.5 concentrations would improve the health of millions around the world – and the most vulnerable populations most of all.


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