Spatiotemporal analysis of contraceptive deserts and adolescent fertility clusters in South Asia: A spatial econometric approach to breaking intergenerational poverty cycles

‘Adolescent fertility’ and ‘teenage motherhood’ are key factors that sustain cycles of poverty across generations in South Asia. Yet there is limited research on how these outcomes are geographically clustered and how ‘contraceptive deserts’, areas with very poor access to family planning, affect nearby regions. This study explores: (i) Where are the geographic clusters of adolescent fertility and teenage motherhood? (ii) How do socioeconomic factors shape these outcomes? and (iii) Do contraceptive deserts create spillover effects in neighboring districts? We tested three hypotheses: H₁: Regions with low female literacy and high child stunting have higher adolescent fertility rates (AFR) and teenage motherhood (TMM). H₂: Internet access has a stronger negative effect on AFR than on TMM. H₃: AFR and TMM show significant spatial autocorrelation (Moran’s I > 0.4). To test these, we identified spatiotemporal clusters of AFR and TMM across South Asia and analyzed their drivers using a spatial econometric approach. Specifically, we applied a dual-outcome Spatial Durbin Model (SDM) to panel data from eight South Asian countries (1990–2023), accounting for spatial lags and spillover effects. The findings show three main results. First, female literacy strongly reduces AFR (β = -1.297, p 0.4) and spillover effects (ρ > 0, p