Extended Use of Nexplanon Implants Placed 3 Years Ago
Yes, a Nexplanon implant placed 3 years ago can be safely continued for an additional 2 years—the 5-year efficacy applies to all currently placed implants, not just newly inserted ones. The FDA now approves Nexplanon for 5 years of use based on clinical trial data demonstrating zero pregnancies during years 4 and 5 of use 1.
FDA Approval and Clinical Evidence
The FDA label (updated 2026) explicitly states that Nexplanon is approved for 5 years of contraceptive use, with clinical trials showing a Pearl Index of 0.0 (95% CI: 0.00-0.69) pregnancies per 100 women-years during years 4 and 5 1.
This approval is based on pharmacokinetic data showing adequate hormone levels throughout the full 5-year period: mean etonogestrel serum concentrations at 3 years were 138-143 pg/mL, at 4 years were 123 pg/mL, and at 5 years were 111 pg/mL—all well above the ovulation suppression threshold 1.
The 5-year duration applies retroactively to implants already in place—there is no biological or pharmacological reason why an implant placed 3 years ago would differ from one placed today, as the hormone release kinetics are identical 1.
Supporting Research Evidence
Multiple independent studies corroborate the extended efficacy:
A prospective cohort study of 291 implant users documented zero pregnancies during 444 woman-years of follow-up in years 4 and 5, with failure rates calculated as 0 per 100 woman-years (one-sided 97.5% CI: 0-1.48 at 4 years; 0-2.65 at 5 years) 2.
An international randomized trial of 390 women using the ENG implant for 5 years showed 100% efficacy in years 4 and 5, with an overall 5-year cumulative pregnancy rate of only 0.6 per 100 women-years 3.
Serum etonogestrel levels remain above the ovulation threshold of 90 pg/mL for all body mass index categories through 5 years of use 2.
Important Considerations for Obesity
Women with BMI ≥30 kg/m² have slightly lower etonogestrel levels (ratio 0.76-0.88 compared to BMI <30), but there is substantial overlap in concentration ranges and no documented pregnancies occurred in this population during extended use 1.
The FDA trial included 152 participants (38.1%) with BMI ≥30 kg/m² and 40 participants (10.0%) with BMI ≥40 kg/m², all of whom maintained contraceptive efficacy through 5 years 1.
Clinical Recommendation
Counsel patients with implants placed 3 years ago that they can safely continue use for 2 additional years without replacement, as the current FDA approval for 5-year duration applies to their existing implant 1. This approach reduces unnecessary procedures, costs, and insertion/removal risks while maintaining highly effective contraception.
The only exception would be if the patient desires pregnancy or has developed a contraindication to progestin-only contraception—in these cases, the implant should be removed regardless of duration 1.