Métodos anticonceptivos de larga duración (LARC): características de las usuarias, tasa de continuidad y efectividad

Abstract

BackgroundLong-Acting Reversible Contraceptive (LARC) methods provide long and reversible contraceptive effects. They include intrauterine devices (IUDs) —copper-containing IUD or levonorgestrel-releasing IUDs— and subdermal implant. Material and methodsA longitudinal observational retrospective study between January 2017 and December 2019 in which clinical records of users of LARC methods of the Elche Health Department were reviewed. Descriptive analyses were performed to describe user characteristics, post insertion problems, unwanted effects, and reasons for discontinuation; Kruskal-Wallis, ANOVA, and Chi-square were performed to compare these variables among different LARC methods, where appropriate. Kaplan-Meier survival curves were constructed to estimate continuation rates and the logrank test was applied for statistical comparisons. Cox proportional hazard models were used to estimate the hazard ratio (HR) for risk of contraceptive method discontinuation due to abnormal bleeding patterns. ResultsWere included 605 LARC method users. These women were generally white, multiparous, and in stable relationships. The most common complications were IUD expulsion (4%) and haematoma at the implant site (42.1%). The main side effect was a change in bleeding patterns (26.8%) and was associated with premature removal (HR=1.76; 95%CI: 1.15-2.68). After 18months of use, the continuation rate was 86.9% (significantly higher for LNG-IUD 52mg) and effectiveness was 99.60% (result of 2 unintended pregnancies with use of copper-containing IUDs). ConclusionsGiven that LARC methods have the highest rates of contraceptive efficacy and continuation, these methods should be the first-line contraceptive methods offered to patients without contraindications.