Overview Contraceptive implants consist of hormone-filled capsules that are inserted under the skin in the woman's upper arm. The first contraceptive implant system developed was the Norplant system, which consists of six thin, flexible capsules made of silicone. Each capsule is 2.4 mm in diameter and 34 mm in length and contains 36 mg of the progestin levonorgestrel. Several other implant systems are currently being tested.
Implants are a safe and effective method of reversible, long-term contraception for most women.
For more information, please see the references in the Annotated Bibliography or the section on new implants on the Contraceptive Research and Development page. Duration of use Norplant implants are effective for five years. Return to fertility Immediately upon removal Also see Hormonal Contraception, IUDs, and HIV Risk.