Objective: World medical societies recommend Long-Acting Reversible Contraception (LARC): high efficacy and positive impact on maternal mortality as a complication of unplanned pregnancy.The objective was to evaluate the maternal mortality rate resulting from complications of unplanned pregnancies, in a public health system, before and after the availability of a LARC (subcutaneous etonogestrel implant). Methods: Statistical analysis using independent tests (Student’s t; Cohen’s d) compared maternal mortality rates resulting from complications of unplanned pregnancies, at menacme and in adolescents, in the periods BEFORE and AFTER the intervention with the etonogestrel subcutaneous implant, in a public health system. Results: Data demonstrated a statistically significant reduction in pregnancy in this population (p=0.042; p=0.003), with practically unchanged data on the maternal mortality rate. Conclusion: Maternal mortality rates may not present statistically significant differences after the availability of a LARC due to adequate assistance for pregnancy complications. However, the subcutaneous implant of etonogestrel has a positive impact on reducing the birth rate at reproductive age, and especially in adolescents, when made widely available by public health systems, which can result in control of maternal mortality resulting from complications of unplanned pregnancies.