Global Trends and Disparities in Maternal Mortality: A Longitudinal Multi-Country Analysis

Maternal mortality is one of the most significant global public health challenges and an important indicator of health-system performance and socioeconomic development. Although substantial reductions have been achieved since 1990, progress has slowed in recent years, and substantial disparities persist across countries and regions.

This longitudinal ecological study used country-level panel data from the Maternal Mortality Dataset compiled by Banerjee (2021), covering 182 countries from 1990 to 2021. Maternal mortality ratio (MMR), expressed as deaths per 100,000 live births, was natural-log transformed for statistical modeling. Human Development Index (HDI) group and continent were included as fixed-effect predictors, while linear mixed-effects models with country-specific random intercepts and random slopes for centered year were used to account for between-country heterogeneity and differences in temporal trajectories.

Maternal mortality declined over the study period (β = -0.029, 95% CI, -0.032 to -0.026; p < 0.001). Compared with the High HDI group, countries in the Low HDI group had higher log(MMR) (β = 1.803, 95% CI, 1.458-2.147; p < 0.001), as did countries in the Medium HDI group (β = 1.042, 95% CI, 0.767-1.317; p < 0.001), whereas the Very High HDI group had lower log(MMR) (β = -1.004, 95% CI, -1.268 to -0.739; p < 0.001). Compared with Africa, log(MMR) was lower in America (β = -0.488, 95% CI, -0.813 to -0.162; p = 0.004), Asia (β = -0.838, 95% CI, -1.134 to -0.542; p < 0.001), Europe (β = -1.698, 95% CI, -2.067 to -1.330; p < 0.001), and Oceania (β = -0.953, 95% CI, -1.404 to -0.502; p < 0.001). Adding random slopes improved model fit (χ ² = 8041.6, df = 2; p < 0.001), indicating heterogeneity in country-specific temporal trajectories. Marginal and conditional R ² were 0.849 and 0.997, respectively.

Maternal mortality declined substantially between 1990 and 2021, but disparities persisted across HDI groups, geographical regions, and countries. The findings highlight the importance of socioeconomic and geographical context when interpreting global maternal mortality patterns and support context-specific approaches to further reduce maternal mortality.