Air Pollution Causes Millions of Preterm and Underweight Births Annually: Study

Exposure to air pollution may be responsible for two-thirds of perinatal complications experienced globally, which includes problems experienced from the start of pregnancy until one year after birth, according to a new study by researchers from the University of California San Francisco and University of Washington.

The findings were published in the medical journal PLOS Medicine on September 28, and are part of a global burden of disease study, which involved a meta analysis of 108 studies, including data from more than 204 countries.

The study focused on total outdoor and indoor air pollution exposure, the later of which is caused by by wood, coal and dung-based cooking stoves, and researchers accounted for negative effects that would taper off at higher levels.

According to the findings, exposure to air pollution contributed to nearly 6 million premature births and nearly 3 million underweight infants born in 2019, which may lead to life-long health issues that continue throughout adulthood.

Researchers indicate that the number of preterm births and underweight infants could be reduced by 78% if air pollution was reduced in Southeast Asia and sub-Saharan Africa, as indoor air pollution is common in these areas, which also have the highest rates of preterm birth in the world.

Developed areas of the world, like the United States, also face risks from ambient air pollution, which may be responsible for roughly 12,000 preterm births per year in this country.

Prior research has highlighted other health risks associated with exposure to air pollution, which may risk of asthma in children, as well as cause elevated blood pressure, even at young ages. Other studies conducted by the same research team found air pollution contributed to the deaths of nearly 500,000 newborns in 2019.

During childhood, side effects of air pollution exposure can result in long-term health problems, including heart disease and increased risk of dementia later in life.

Preterm birth is the leading cause of neonatal mortality worldwide. More than 15 million infants are born preterm every year, and the World Health Organization indicates roughly 90% of the world’s population lives in heavily polluted areas.

This is the first global burden of disease study to focus on the effects of indoor air pollution, not just outdoor air pollution. Indoor air pollution commonly comes from sources like cooking stoves, which accounted for two-thirds of the measured effects in this study.

Researchers said this is the most in-depth study on how air pollution affects factors during pregnancy, including gestational age at birth, reduction in birth weight, low birth weight and preterm birth.

“Our study suggests that taking measures to mitigate climate change and reduce air pollution levels will have significant health co-benefit for newborns,” researchers concluded.