BACKGROUND: Vaccination plays a pivotal role in safeguarding the health and wellbeing of children worldwide, preventing the spread of infectious diseases, and reducing mortality rates. Despite significant progress in global immunisation efforts, disparities in vaccination coverage persist in Madagascar. This study examines the factors associated with full vaccination coverage among children aged 12-23 months in Madagascar. METHODS: We analysed a cross-sectional dataset from the 2021 Madagascar Demographic and Health Survey (MDHS). A total of 2,250 mothers with children aged 12 to 23 months were extracted from the children's dataset. Vaccination coverage was evaluated based on maternal self-report and child vaccination card observations. A weighted multivariable binary logistic regression analysis was used to examine the factors associated with full vaccination coverage. Adjusted odds ratios (aORs) with 95% confidence intervals (CIs) were used to present the results of the factors associated with full vaccination coverage. Stata 13.0 was used to perform all the analyses. RESULTS: We found that 48.9% of children aged 12-23 months were fully vaccinated. Vaccination coverage for Bacille Calmette-Guérin (BCG), third-dose polio, third-dose of diphtheria-tetanus-pertussis (DPT), and measles was 78.1%, 58.6%, 68.4%, and 63.9%, respectively. Mothers aged 35 to 49 (aOR: 1.69
95% CI: 1.08-2.64) were more likely to have their children fully vaccinated compared to women aged 15-24. Children born to mothers with secondary or higher education (aOR:1.68
95% CI:1.15-2.45) were more likely to receive full vaccination than those whose mothers had no formal education. Mothers within the middle-class wealth index (aOR: 1.48
95% CI: 1.04-2.12) were more likely to have their children fully vaccinated compared to the poorest category. Mothers who were working (aOR: 1.45
95% CI: 1.06-1.98) had higher odds of full childhood vaccination compared to those who were not working. Compared to mothers who delivered their babies at home or other places, those who delivered their babies at the health facility (aOR:1.57
95% CI: 1.22-2.02) were more likely to vaccinate their children . Mothers who had less than eight (1-7) antenatal care visits (aOR: 3.63
95% CI: 2.30-5.72) and those with 8 or more visits (aOR: 1.20
95% CI: 1.35-6.51) were more likely to have their children vaccinated fully compared to those with zero antenatal care visits. Mothers exposed to media (aOR: 1.65
95% CI: 1.26-2.16) were more likely to fully vaccinate their children than their unexposed counterparts. CONCLUSION: Full childhood vaccination coverage is low in Madagascar. Factors identified to be associated with vaccination coverage were maternal age, education, place of delivery, working status, antenatal care visits, and media access. Collaboration between the Ministry of Health and local authorities is recommended in Madagascar to improve vaccination coverage, promote antenatal care, clean delivery practices and access to skilled birth attendants, raise parental awareness, and enhance healthcare workers' communication about vaccination schedules through various media channels.