Child morbidity remains a major barrier preventing Bangladesh from achieving the Sustainable Development Goals (target 3.2), despite notable reductions in child mortality. Consequently, greater attention to child health–related conditions is essential. Accordingly, this study seeks to examine the prevalence of morbidity among children under five years of age in Bangladesh and to identify the factors associated with it. This study utilized secondary cross-sectional data from the Bangladesh Demographic and Health Survey 2017–2018, which employed a two-stage systematic sampling framework to collect information. Following tests of association, a Bayesian binary logistic regression model was applied to determine significant risk factors for morbidity among under-five children, and convergence of the simulation was assessed using trace plots. The prevalence findings indicate that more than one-third of under-five children in Bangladesh experienced at least one child health–related condition, with the highest proportion of morbidity observed in the Barisal division (approximately 42%). Results from the Bayesian logistic regression suggest that increasing child age and higher levels of maternal education are linked to a reduced likelihood of child morbidity in Bangladesh. Furthermore, male children exhibited a 7% greater risk of morbidity compared with female children. In addition, underweight children were found to have a 31% higher risk of fever, diarrhea, or acute respiratory infection (ARI)–related conditions than their counterparts. The findings of this study demonstrate that child morbidity continues to pose a serious challenge in Bangladesh. Therefore, policymakers should prioritize interventions targeting key risk factors, including maternal education and child nutritional status.
