Household water, sanitation, and hygiene access and its impact on nutritional outcomes in children under five: evidence from Pakistan

Background: Child undernutrition is a critical public health issue in Pakistan. While multiple factors contribute to undernutrition, the role of household-level access to Water, Sanitation, and Hygiene (WASH) services remains inadequately explored. This study aims to examine the relationship between household WASH services access and the nutritional status of children under five. Methods: This cross-sectional study utilised data from the Pakistan Demographic and Health Survey (PDHS 2017-18). Household WASH services access was the primary independent variable categorised using WHO/UNICEF JMP scale, while child nutritional outcomes, including stunting, wasting, and underweight, were taken as dependent variables. Multivariate logistic regression was used to evaluate these associations, with adjustments made for potential confounders. Data analysis was conducted using R Studio. Results: The prevalence of stunting, wasting, and underweight in the study cohort was 38%, 8%, and 21.6%, respectively. In adjusted analyses absence of water service (aOR = 1.52; 95% CI: 1.01–2.26; p = 0.041), basic sanitation (aOR = 1.38; 95% CI: 1.07–1.63; p = 0.040) and hygiene facilities (aOR = 1.66; 95% CI: 1.34–2.25; p = 0.036) were associated with higher odds of underweight. Similarly, lack of hygiene facilities (aOR = 1.61; 95% CI: 1.07–2.44; p = 0.023) and water service (aOR = 1.49; 95% CI: 1.01–2.21; p = 0.046), and unimproved sanitation facilities (aOR = 1.30; 95% CI: 1.03–1.65; p = 0.027) increased the odds of stunting in children under five. However, no significant association was found between WASH indicators and wasting. Child age, low maternal education, recent diarrheal illness, and household poverty were among other strong predictors of undernutrition. Province-wise analysis revealed that higher undernutrition coincided with poorer household-level WASH access, particularly in Balochistan, FATA, and Sindh, while GB and ICT showed both better services and outcomes. Conclusion: Inadequate household-level access to water, sanitation, and hygiene services is significantly associated with higher odds of underweight and stunting in Pakistani children under five. However, household WASH services access was not significantly associated with wasting. Targeted WASH interventions may help reduce chronic undernutrition, especially in underserved regions.