Prevalence and Predictors of Delayed and Missed BCG Immunization among Children Aged 12–23 Months in Ajmer District of Rajasthan: A Cross-Sectional Study

Background: Delayed and missed Bacillus Calmette–Guérin (BCG) vaccination remains a public health concern in India. This study assessed the prevalence and predictors of delayed and missed BCG immunization among children aged 12–23 months in Ajmer district, Rajasthan. Materials and Methods: A cross-sectional analytical study was conducted at the Immunization Clinic of JLN Medical College, Ajmer, from August 2023 to December 2024. A total of 273 children aged 12–23 months were enrolled by consecutive sampling. Data were collected via a pretested, semi-structured, interviewer-administered questionnaire; vaccination timing was verified using the Mother and Child Protection (MCP) card. Bivariate and multivariate logistic regression analyses were performed using Statistical Package for the Social Sciences version 20.0 (IBM Corp., Armonk, NY, USA). Variables with P < 0.20 in bivariate analysis were included in multivariate models. Results: Among the 273 children, 12.1% had missed and 22.7% had delayed BCG vaccination. Absence of the MCP card (odds ratio [OR] = 9.89), noninstitutional delivery (OR = 0.29), and access barriers (OR = 1.88) were key bivariate predictors. In multivariate analysis, working mothers (adjusted OR [AOR] = 0.29; P = 0.006) and maternal age ≥30 years (AOR = 0.22; P = 0.001) were independently protective against missed BCG. No variable was independently associated with delayed BCG vaccination. Conclusion: Missed and delayed BCG immunization remain significant challenges in Ajmer district. Strengthening MCP card utilization, ensuring birth-dose vaccination, and improving outreach are critical. Strengthening birth-dose delivery systems and MCP card-based tracking can significantly improve immunization timeliness.