INTRODUCTION:
childhood immunization prevents millions of deaths annually and is essential for achieving sustainable development goals. Ghana has been an immunization success story in sub-saharan Africa, but recent trends in coverage and equity remain poorly characterized. This study examined temporal trends and socioeconomic inequalities in childhood immunization from 1998 to 2022.

METHODS:
we analysed four rounds of the Ghana Demographic and Health Surveys (1998, 2008, 2014, 2022) including 4314 children aged 12-23 months. Full immunization was defined as receipt of BCG, three doses each of DPT and polio vaccines, and measles vaccine. Wealth-related inequalities were assessed using concentration index, slope index of inequality, and relative index of inequality. Survey-weighted logistic regression identified determinants of immunization status. Oaxaca-Blinder decomposition quantified contributions to coverage changes.

RESULTS:
full immunization coverage increased from 64.0% (95% CI: 59.8-68.2) in 1998 to 80.8% (77.0-84.6) in 2008, then declined to 74.7% (72.2-77.2) by 2022. Wealth-related inequality decreased substantially from concentration index of 0.027 (0.004-0.050) in 2008 to 0.001 (-0.017 to 0.018) in 2014, indicating near-perfect equity. However, by 2022, inequality had re-emerged (CI = 0.048, 95% CI: 0.034-0.063), with coverage among the poorest quintile dropping from 78.8% to 66.1% while the richest maintained 83.9%. Mother's education was the strongest predictor of immunization (OR = 1.54 for secondary education, 95% CI: 1.20-1.98).

CONCLUSIONS:
Ghana achieved remarkable immunization equity by 2014, but recent years show concerning reversal with the poorest children increasingly left behind. Targeted interventions focusing on less-educated mothers in poorest households are urgently needed to restore equity gains and progress toward universal coverage.