Babies Born to Mothers Exposed to Polluted Air are at Higher Risk for Childhood Pneumonia
Pregnant women are given detailed instructions by doctors to maximize their baby’s health, from what they should eat to activities they should avoid. But what about the air moms-to-be breathe?
In regions where solid fuel use for cooking is most prevalent – Africa and South Asia – pregnant women often breathe in the toxic smoke from cooking over inefficient stoves that burn polluting fuels while preparing their family meals. A growing amount of research shows that pre- and post-birth exposure to household air pollution (HAP) greatly increases newborns’ risk for developing deadly health complications, such as pneumonia, a leading cause of death in children under five.
In 2019, lower respiratory infections, like pneumonia, caused over 650,000 deaths in children under five. Household air pollution from solid fuel use for cooking is tied to over one third of these deaths. While we know that exposure to HAP has devastating impacts on child health, we lack a nuanced understanding of the relationship between pre- and post-birth HAP exposure and childhood pneumonia.
A research study, co-funded by Clean Cooking Alliance, the National Institute of Environmental Health Sciences and the Thrasher Research Fund, recently set out to shine a light on the global burden of pneumonia associated with HAP in Ghana.
Researchers quantified the relationship between pre- and post-birth exposure to HAP and risk of developing pneumonia in the first year of life. To do this, researchers measured how much household air pollution, in parts per million of carbon monoxide , babies were exposed to, both in the womb and after being born. Babies were then regularly checked for pneumonia during their first year of life. This enabled researchers to look at how much a baby’s risk of developing pneumonia changes with increases in exposure to household air pollution, both in the womb and after being born. This research was part of the Ghana Randomized Air Pollution and Health Study, a larger research effort focused on evaluating the effectiveness of clean fuel interventions in Ghana.
The study found that pre-birth exposure to HAP increased the risk of pneumonia more than post-birth exposure, highlighting that babies still in the womb are especially vulnerable to the deadly impacts of HAP.
Researchers found that with a seemingly small increase in average pre-birth exposure (1 part per million of carbon monoxide) to HAP, the risk of pneumonia increased by 10% and the risk of severe pneumonia by 15%. Meanwhile, the same increase in average post-birth exposure to HAP was found to be associated only with an increased risk of severe pneumonia (by 6%). To add some more context, the World Health Organization recommends limiting exposure to carbon monoxide to just 4 parts per million over 24-hours, so even a 1 part per million increase can be health damaging.
Additionally, it was found that baby girls were more susceptible to the impacts of being exposed to HAP, especially while in the womb. For a given increase in pre-birth exposure, baby girls were significantly more at risk of developing pneumonia than baby boys.
“It’s exciting to see the data of this pivotal study out now. This data comes out of a study area where most pregnant women and their families use biomass fuel for an essential part of their livelihood – cooking. Our data provides evidence to support decisions to actively promote use of cleaner fuels as an additional tool to prevent childhood pneumonia. We are grateful to all the community members, study participants, funders and the team of researchers who invested significant time and efforts to arrive at these results today,” says Dr. Kwaku Poku Asante, who co-led this research effort.
This study provides robust evidence that pre- and post-birth HAP exposure increases the risk of early childhood pneumonia, but more studies are needed to bolster the results.
Because HAP is a complex problem that persists in many communities around the world, future research into other populations and metrics would be valuable to cementing these current findings.
Collectively, these findings suggest that clean cooking interventions implemented prior to pregnancy could save lives by improving the quality of the air moms-to-be breathe, and ensure that no mom worries about her child growing up in a toxic, polluted environment:
“Findings from our study suggest that infants will be less likely to suffer from pneumonia in their first year if their mothers breathe cleaner air during pregnancy. Policies to reduce exposure to biomass cook smoke during pregnancy hold tremendous promise to improve infant health.” says Dr. Patrick Kinney, who led the study.
By reducing household air pollution throughout pregnancy and after birth, clean cooking interventions can play a critical role in reducing the risk of early childhood pneumonia and saving children’s lives. Access to clean cooking means that mothers who already work tirelessly to ensure their child’s health have one less danger to worry about. It could also have potential to increase women’s well-being and health specifically, since girls were found to be the most vulnerable. Policies that promote the sustained adoption of clean cooking technologies prior to these vulnerable stages of life could help maximize the health benefits associated with breathing clean air and greatly increase life expectancy for infants.
 Carbon monoxide is a gas released by polluting fuels and technologies, in amounts exceeding guidelines from the World Health Organization, and is commonly used as a measure of household air pollution.