Effectiveness and continuation rates of the etonogestrel-subdermal contraceptive implant versus short-acting contraceptive methods offered at no cost in Campinas, Brazil.

Abstract

To compare the efficacy, reasons for discontinuation and continuation rates of the etonogestrel (ENG)-subdermal contraceptive implant when offered at no cost, and the basis of free choice versus short-acting reversible contraceptive (SARC) methods including combined oral contraceptives (COCs), once-a-month injectables, vaginal ring, and patch. We conducted a prospective study at the University of Campinas, Brazil, involving women aged 18 to 40 years. They were counseled on various contraceptive methods before entering the study and followed up every 3 months for up to 24 months. Satisfaction was assessed using a Likert scale. Survival rates were estimated using the Kaplan-Meier test, and curve comparisons were performed using the log-rank test. We enrolled 609 women including 358/609 women (58.8%) who chose the ENG-implant and 251/609 (41.2%) who chose SARC methods. Contraceptive failure and all other reasons for discontinuation were significantly higher in SARC users compared to the ENG-implant users (P < 0.001 and P = 0.002, respectively). The continuation rate was higher among ENG-implant users (89.9% and 75.4%) compared to SARC methods users (27.2% and 15.9%) up to 1 and 2 years after study initiation, respectively. Satisfaction was high in both groups (>82%). The ENG-implant showed higher contraceptive effectiveness and higher continuation rates than SARC methods up to 2 years after study initiation. Furthermore, users from both groups were highly satisfied with their contraceptive. The main reason for discontinuing use of the ENG-implant was bothersome uterine bleeding, while for SARC methods it was for personal reasons.