Two factors of the climate crisis, air pollution and rising temperatures, appear to be particularly affect pregnant women and their babies. American researchers found a clear link between these phenomena and problematic births. They call for structural action to combat the climate crisis.

When the climate crisis comes up, it is often about extreme weather events such as forest fires and severe storms. But a large-scale study, published in the medical journal Journal of the American Medical Association (JAMA), examined the impact of more common factors: air pollution and heat. As for air pollution, the scientists looked at ozone (or smog) and certain fine dust particles called PM 2.5.

Preterm or low birth weight

The study analyzed the conclusions of 68 separate studies conducted in different parts of the United States, the data of which went back to 2007. In total, about 32 million births were examined. 58 studies focused on air pollution and ten on exposure to heat. Of the air pollution studies, 84% found that women in more polluted areas were at greater risk of problematic pregnancy. The same was true for nine out of ten studies that focused on the effects of heat exposure.

Most of the studies examined the risks of preterm births or newborns with low birth weight. These babies can have lifelong consequences, such as increased susceptibility to disease and disrupted brain development. Some studies focused on miscarriages and they too were able to make the same connections.

High-risk groups

Mothers with asthma were found to have a significantly increased risk of problematic pregnancy due to air pollution. African-Americans and minorities are also disproportionately affected, according to the scientists, presumably because they are more likely to live near factories or highways.

Moreover, the districts where they are strongly represented are more often called ‘heat islands’, where temperatures rise more easily due to a shortage of greenery and an excess of materials such as asphalt and concrete.

Systematic solutions needed

“You could really argue that a whole generation of children are born bearing the effects of pollution,” explained lead author Nathaniel DeNicola. “We can give pregnant women advice, but they can’t control the temperature outside and the air pollution. The real solutions are therefore systematic solutions, which are primarily in the hands of policy makers.” In their conclusions, the scientists call for effective action to stop the climate crisis.

Angie Mahecha

An fitness addict passionate about all things nature and animals, Angie often volunteers her time to NGOs and governmental organizations alike working with animals in general and endangered species in particular. She covers stories on wildlife and the environment for the Scientific Origin.