Background: This study was conducted to compare the incidence of repeat teenage pregnancy over a 24-month period postpartum among users of Implanon, the combined oral contraceptive pill (COCP) or depot medroxyprogesterone acetate (DMPA) and barrier methods or nothing (barrier/none). Contraceptive continuation rates 24 months postpartum for Implanon and COCP/DMPA were also compared.
Study design: A prospective cohort study was conducted. Comparison groups were postpartum teenagers (12-18 years old) who self-selected Implanon (n=73), COCP/DMPA (n=40) and barrier/none (n=24). Questionnaires were used to gather data at recruitment and postpartum at 6 weeks and then 3 monthly intervals for 2 years.
Results: At 24 months postpartum, 48 (35%) teenagers had conceived. Implanon users became pregnant later than other contraceptive groups (p=.022), with mean time to first repeat pregnancy of 23.8 months [95% confidence interval (CI), 22.2-25.5], compared to 18.1 months (95% CI, 15.1-20.7) for COCP/DMPA and 17.6 months (95% CI, 14.0-21.3) for barrier/none. Implanon users were more likely to continue their use at 24 months than COCP/DMPA (p<.001) users. The mean duration for Implanon users was 18.7 months (95% CI, 17.0-20.3) compared to 11.9 months (95% CI, 9.5-14.3) for COCP/DMPA.
Conclusion: Teenagers who choose Implanon are significantly less likely to become pregnant and were found to continue with this method of contraception 24 months postpartum compared to those who choose COCP or DMPA and barrier methods or nothing.