Spatial variations and geographic determinants of postnatal care utilization in Sub-Saharan Africa: a multiscale geographically weighted regression

Postnatal care (PNC) has substantial potential to reduce maternal and neonatal mortality through the early detection and management of complications. However, few studies have examined the spatial variation and determinants of postnatal care utilization in sub-Saharan Africa (SSA). Hence, this study aimed to identify geographical variations and predictors contributing to postnatal care utilization in SSA. The study utilized the DHS dataset from 28 SSA countries (2015-2024), with a weighted sample of 200,935 women of reproductive age. Global Moran's I was used to assess spatial autocorrelation, while Getis-Ord Gi* statistics identified hotspot and coldspot areas of postnatal care utilization. Global regression models (ordinary least squares, spatial lag, and spatial error) and local regression models (geographically weighted regression and multiscale geographically weighted regression) were fitted to determine predictors of postnatal care utilization. Model performance was evaluated using corrected Akaike information criterion (AICc) and adjusted R², and significant spatial predictors were mapped. The spatial distribution of postnatal care utilization in SSA showed significant clustering (Moran's I 0.49, z-score 109.1, p < 0.01). Significant coldspot areas were identified in regions of Ethiopia, Kenya, Uganda, Rwanda, Burundi, Tanzania, South Africa, Lesotho, Nigeria, Côte d'Ivoire, Angola, and Mauritania. Whereas Senegal, Guinea, Sierra Leone, Gambia, Burkina Faso, Gabon, Cameroon, Malawi, Mozambique, Zambia, Zimbabwe, and Madagascar exhibited hotspot patterns. Facility delivery, media exposure, antenatal care utilization, and secondary or higher education were significant predictors of postnatal care utilization. Women from lower wealth categories demonstrated higher utilization patterns in some geographic regions. MGWR captured spatially varying relationships more effectively than global models. Spatial variation of postnatal care utilization was clustered and varied across regions in SSA. Key hotspot and coldspot areas were identified, each associated with distinct geographic predictors. This study's findings have significant implications for efforts to improve maternal and child health in SSA.