Air Pollution and Warming Tied to Maternal Mortality Across Asia–Pacific

Maternal mortality in the Asia–Pacific region is not only a national problem but a shared regional one, according to a new spatial analysis published in BMC Public Health. The study, which examined panel data from 42 countries between 2005 and 2024, found strong positive spatial dependence in maternal mortality, meaning that maternal health outcomes in one country are statistically linked to those in neighbouring countries. The finding suggests that environmental and health conditions cross borders in ways that purely national maternal health strategies may fail to capture.

The researchers, led by Bazzil Muzaffar Khan and colleagues, used a Dynamic Spatial Durbin Model estimated with quasi-maximum likelihood to assess how air pollution, climate variables, renewable energy use, and socioeconomic conditions relate to maternal deaths. To capture the geography of these relationships, the team computed spatial interactions using two alternative spatial weight matrices: Inverse Distance Weighting, which weights neighbouring countries by how far away they are, and a K-Nearest Neighbors specification with six neighbours, which links each country to its six closest counterparts. Diagnostic tests supported the presence of spatial dependence in the data, underpinning the choice of the spatial modelling framework.

The results point to a consistent environmental signal. Air pollution showed a positive and statistically significant association with maternal death, and greenhouse gas emissions were also found to exacerbate the risk to maternal health. Temperature had a positive association with maternal mortality, with the Inverse Distance Weighting specification indicating that warmer temperatures accompany higher maternal mortality, although the magnitude of this effect depended on which spatial weighting scheme was used. The authors present these as associations within an observational panel, not as proof of causation, and the sensitivity of the temperature estimate to the weighting scheme is one reason for caution in interpretation.

Socioeconomic factors moved in the opposite direction. Maternal mortality was significantly lower in countries with higher population density and higher GDP per capita, a pattern the researchers attribute to better access to health services and infrastructure and to broader economic development. Renewable energy use showed a strong and significant mitigative association, which the authors interpret as evidence of its potential to reduce the health impacts arising from environmental factors.

One result stands out as less intuitive: healthcare spending showed a positive association with maternal mortality, but the authors note that this finding was model-specific and therefore should be read with care. The study does not resolve why this pattern appears, and the authors flag the result explicitly rather than presenting it as a settled effect, which is a useful reminder that coefficients in spatial panel models can shift with specification choices.

The study’s scope and limitations matter for how the findings should be used. The analysis covers 42 Asia–Pacific countries over two decades and relies on country-level panel data, so it captures associations at the national scale rather than individual-level pathways from pollution exposure or heat to maternal death. The two spatial weight matrices produced broadly consistent conclusions for most variables, but the dependence of some estimates on the weighting scheme, and the model-specific healthcare spending result, mean the findings are strongest where the specifications agree.

Despite substantial progress in reducing maternal deaths worldwide, the region remains a major centre of the global burden, and the authors argue that environmental degradation, climate change, and socioeconomic inequality continue to shape maternal health there. Their conclusion is that maternal health strategies in the Asia–Pacific should incorporate environmental sustainability, climate adaptation, and regional cooperation. They point specifically to accelerated transitions toward renewable energy, reduced air pollution and greenhouse gas emissions, and more coordinated cross-border health and environmental policies as levers that could help lower maternal mortality across the region.

For policymakers, the spatial dependence finding may be the most consequential element. If maternal mortality in one country tracks conditions in its neighbours, then maternal health outcomes appear to move together across the region. The study does not test specific interventions, and its observational design cannot establish that cutting emissions in one country would reduce maternal deaths in another, but it does provide a quantitative map of where maternal health outcomes move together. As the authors suggest, that geography may be a reason to treat maternal health as a regional, not merely national, policy problem.

Subject of Research: Spatial analysis of air pollution, climate, and socioeconomic determinants of maternal mortality in 42 Asia–Pacific countries

Article Title: Exploring the spatial nexus between air quality, climate change, and socioeconomic determinants of maternal mortality across the Asia–Pacific region

Article References: Khan, B. M., Khurshid, N., Egbe, C. E., Khan, E. A., & Nawaz, R. (2026). Exploring the spatial nexus between air quality, climate change, and socioeconomic determinants of maternal mortality across the Asia–Pacific region. BMC Public Health. https://doi.org/10.1186/s12889-026-29867-9

Image Credits: AI Generated

DOI: 10.1186/s12889-026-29867-9

Keywords: maternal mortality, air pollution, climate change, Asia-Pacific, spatial analysis, Dynamic Spatial Durbin Model, greenhouse gas emissions, renewable energy, public health, panel data, healthcare spending, regional cooperation