Vaccination in all age groups corresponds to a strategy that has had a great impact on reducing morbidity and mortality rates due to vaccine-preventable diseases over the years. Despite being free and mandatory, there are still gaps that prevent reaching the coverage goals necessary to avoid outbreaks and eradicate these diseases. Therefore, the objective of this study was to determine the factors that are associated with non-compliance with the vaccination schedule in children under 36 months of age who attended the IPRESS I-4 of the Iquitos and Punchana microgrid during the months of August - November 2023. A total of 270 surveys were analyzed, where 90 cases of undervaccinated children were analyzed compared to a total of 180 controls. Factors significantly associated with non-compliance with the vaccination schedule were found as sociodemographic factors: low educational level (p=0.0...