Estimated effect of age of marriage on utilisation of India's Integrated Child Development Service programme

Background Age of marriage among women is considered an important indicator of their readiness for familial integration and parenting. This study estimated the effect of age of marriage of young mothers (aged 15-24 years) on utilisation of various services for their children, provided under the Integrated Child Development Service (ICDS) programme in India.Methods Data from the nationally representative 2019-2021 National Family Health Survey of India were analysed. Mothers' age of menarche was used as an instrumental variable to isolate the effect of age of marriage on whether their children received (1) food, (2) health check-up, (3) immunisation, (4) early childhood care or preschooling or (5) weight measurement services from ICDS.Results Nationally, 67.9% (95% CI 67.6%, 68.3%) of children received food (sample: 60 578), 61.8% (95% CI 61.4%, 62.1%) received a health check-up (sample: 60 316), 60.0% (95% CI 59.6%, 60.4%) received immunisation services (sample: 60 537), 52.0% (95% CI 51.6%, 52.4%) received early childhood care or preschooling (sample: 60 458) and 62.9% (95% CI 62.5%, 63.3%) received weight measurement services (sample: 60 278). Findings from instrumental variable analysis suggest that a 1-year increase in age of marriage could yield a 9 percentage point increase (95% CI 4%-13%; p<0.001) in utilisation of immunisation services. Although postponement of marriage positively affected utilisation of each of the other four ICDS components, these effects were not statistically significant.Conclusion Postponing age of marriage among young women is an effective intervention for promoting uptake of child immunisation services. Our findings support the Government of India's 2021 Bill to raise legal age of marriage of women.