Vitamin A supplementation (VAS) is a widely implemented public health intervention aimed at reducing childhood mortality, particularly in resource-limited settings. A comprehensive search strategy was employed using multiple databases and references. Studies were selected based on predefined criteria, including sample size, study design, and outcomes related to VAS and pre-weaning mortality. The review identified a significant reduction (p < 0.05) in the proportion of pre-weaning deaths associated with VAS supplementation among smallholder farmers. VAS is effective in reducing pre-weaning mortality rates, particularly in rural settings where vitamin deficiencies are prevalent. Further research should focus on longitudinal studies to assess sustained effects and explore potential mechanisms for the observed outcomes. Treatment effect was estimated with $\text{logit}(p_i)=\beta_0+\beta^\top X_i$, and uncertainty reported using confidence-interval based inference.