(Updated June 2014)
The implant is a progestin-only long-acting reversible contraceptive method. It consists of a single, matchstick-sized rod that contains the progestin etonogestrel (the same progestin contained in the vaginal ring). There are two versions of the implant: NEXPLANON® and Implanon®. NEXPLANON® is the second generation of this implant. It contains barium to allow localization with X-ray as well as a new inserter. Size, active medication, and side effect profile are unchanged from Implanon®. The implant is effective for 3 years and is a good contraceptive choice for women who cannot use estrogen.
The contraceptive implant is inserted in the subdermal tissue of the
inside aspect of the upper non-dominant arm. Once placed, it is not visible but is usually palpable. The rod must be inserted and removed by a trained provider. Because the insertion of the rod involves no incision, it is quick (less than 1 minute) and relatively painless.37 The implant must be removed within 3 years of insertion—a procedure that takes about 3 minutes. A new implant may be inserted in the same arm, and through the same incision from which the previous implant was removed.
This method is extremely effective, with a failure rate of 0.05 percent.37
There is no evidence of connection between weight and effectiveness for the arm implant.38
As with other progestin-only methods, irregular endometrial bleeding and amenorrhea are common. In clinical studies, the bleeding patterns observed in women were irregular37 and included:
- Bleeding irregularities, including infrequent bleeding (33.6%), amenorrhea (22.2%), prolonged bleeding (17.7%), and frequent bleeding (6.7%).
- One study found that ethinyl estradiol may help control bleeding during the first few months of implant use.
- Other side effects that led to discontinuation include weight gain (2.3%), emotional liability (2.3%), headache (1.6%), acne (1.3%), and depression (1.0%)37
Contraindications and Precautions
|Medical Eligibility Criteria for the Contraceptive Implant|
(unacceptable health risk if the contraceptive method is used)
(theoretical or proven risks usually outweigh the advantages of using the method)
Source: Reference 5
- High efficacy
- Rapid reversibility: after implant is removed, most women (94%) ovulate by 3 months, the majority within 3 weeks
- Rapid procedure: insertion takes one minute and removal takes three minutes
- Can use when lactating as soon as six weeks postpartum
- Non-contraceptive benefits, such as improved dysmenorrhea and possibly acne
- Requires visit to trained clinician for insertion and removal
- Irregular bleeding patterns
- No protection against STIs
- The implant provides 3 years of continuous pregnancy prevention and must be removed within 3 years; a new rod can be inserted at the time of removal.
- Once placed, the implant is not visible but is usually palpable. (Providers may want to show women the implant and briefly describe the insertion and removal process.)
- The contraceptive implant can cause bleeding irregularities, including amenorrhea.
- Non-hormonal back-up contraception is needed for the first 7 days after insertion.
- This method does not protect against STIs.
About Audrey Kelly, PharmD