Nexplanon Dosage and Administration
Device Specifications and Dosing
Nexplanon is a single-rod subdermal implant containing 68 mg of etonogestrel that provides effective contraception for up to 3 years. 1, 2, 3
- The implant is 4 cm long, made of ethylene vinyl acetate copolymer (non-absorbable material), and contains 15 mg of barium sulfate for radiographic visualization 2
- It releases approximately 120 μg of etonogestrel daily (the active metabolite) 1
- The device comes pre-loaded in a sterile applicator for single-use insertion 3
Insertion Timing and Technique
Timing of Insertion
The implant can be inserted at any time if it is reasonably certain the woman is not pregnant. 1
Optimal timing based on clinical scenario: 1
- Within first 5 days of menstrual bleeding: No backup contraception needed
- Day 6 or later of menstrual cycle: Requires 7 days of backup contraception (abstinence or barrier method)
- Postpartum (breastfeeding): Can insert anytime ≥1 month postpartum without backup if amenorrheic and fully/nearly fully breastfeeding; otherwise requires 7 days backup 1
- Postpartum (not breastfeeding): Can insert immediately or anytime; if ≥21 days postpartum and menstrual cycles have not returned, requires 7 days backup contraception 1
- Post-abortion: Can insert within first 7 days (including immediately) without backup contraception needed 1
Insertion Procedure
Mean insertion time is approximately 0.5-1.1 minutes. 3, 4
- Position the applicator needle subdermally in the inner aspect of the non-dominant upper arm 3
- Withdraw the cannula, leaving the implant rod in place 3
- Insertion complications are extremely rare (0.3% incidence) 3
Duration of Use and Removal
The implant provides effective contraception for 3 years and must be removed or replaced after this period. 1, 2, 4
Removal Procedure
- Mean removal time is approximately 2.6-3.5 minutes 3, 4
- Use the "pop out" technique involving a 2-mm incision 3
- Removal complications are rare (0.2% incidence) 3
- Return to normal menstrual cycles and fertility is rapid after removal 4
Efficacy
Nexplanon has a failure rate of less than 1 per 100 woman-years, with no pregnancies reported in major clinical trials. 1, 5, 4
- In one U.S. study with 474 woman-years of exposure, zero pregnancies occurred 4
- Continuation rate at 12 months is approximately 93.8% 6
Common Pitfalls to Avoid
Do not confuse the timing requirements for backup contraception—the critical threshold is whether insertion occurs within the first 5 days versus day 6 or later of the menstrual cycle. 1
- Failure to provide adequate counseling about expected bleeding pattern changes is the most common reason for discontinuation (13% of users) 4
- Most women experience infrequent bleeding patterns (most common) rather than frequent bleeding (least common), with amenorrhea rates of 14-20% during months 4-24 4
- Deep insertion should be avoided as it complicates removal 3