Trends in childhood routine immunisation and maternal health service access and utilisation in Sokoto State, Nigeria. A quantitative survey

Sokoto State, Nigeria, continues to report some of the lowest maternal, neonatal, and child health (MNCH) indicators nationally. The COVID-19 pandemic further disrupted service delivery in Nigeria, yet its long-term impact on routine immunisation (RI) and maternal health services at the sub-national level in fragile and resource-constrained settings remains underexplored. We conducted a retrospective cohort study using secondary administrative data from 2015 to 2023 to examine the trends in the uptake of the first and third doses of the diphtheria-tetanus-pertussis containing vaccines (DTP-1 and DTP-3), and facility-based deliveries. Dynamic time-series regression models were applied to assess the influence of the COVID-19 period and contextual factors, including climate change, settlement type, and health budgets. DTP-1 coverage and proportion of facility deliveries improved over time. There was a significant increase in facility deliveries during the COVID-19 pandemic (p = 0.019), while DTP-1 coverage declined modestly during the pandemic (p = 0.030). DTP-3 showed no significant change (p = 0.078). Urban residence was positively associated with facility delivery. Lagged dependent variables were strongly significant across the models, indicating path dependency in service utilisation. These findings highlight both resilience and vulnerability within Sokoto’s healthcare system. While maternal services were adapted during the pandemic, immunisation continuity remained fragile. These insights could inform the development of a pandemic-resilient framework for MNCH services in similar settings.