Background: In Chile, contraceptive methods are essential to prevent unwanted pregnancies and STIs. Over time, public policies have been established to promote the correct use of contraceptives, however, there is little evidence of the effectiveness of the measures used. Objectives: To determine the progression of the contraceptive methods used in the population under control in Chile and the effectiveness in contraception and STI prevention, based on data extracted from the REM between 2012 and 2016. Materials and method: The research is quantitative, with an observational design, descriptive correlational scope and retrospective longitudinal cut. Information extracted from the DEIS corresponding to the REM is used and the analysis is carried out using Microsoft Excel. Results: An increase in the use of contraceptives was observed, with a progressive decrease in the use of female and male condoms was observed, presenting a use of less than 5% in the years evaluated. In addition, there is a decrease in the use of oral contraceptives, increasing injectables and implants. Concerning unwanted pregnancies, less than 50% were desired. Regarding STIs, condyloma prevails, with an increase over the years in discharges due to abandonment. Conclusion: The study constitutes a tool for the analysis of the Chilean population and the importance of public measures and campaigns to generate impact and combat the prevalence of unwanted conception and STIs.