Each implant is a plastic rod about the size of a matchstick. The rods contain a form of the hormone progesterone called etonogestrel.
What to Expect at the Doctor's Office
After numbing your skin, a health care provider inserts the rod under the skin of your upper arm, using a device that pushes the rod through a needle.
The insertion process may take less than a minute. Afterward, you should be able to feel but not see the implant under your skin.
You can use a birth control implant for up to three years. Then it needs to be replaced.
Removing it is generally easy. It may take only a few minutes or 20 minutes, depending on how much scar tissue has developed. Your health care provider numbs your skin and makes a tiny incision near the tip of the implant, then pulls it out.
Implanon vs. Nexplanon
The drug manufacturer, Merck, is phasing out Implanon and replacing it with Nexplanon.
The two implants are nearly identical, but the insertion device for Nexplanon is simplified and avoids deep placement of the implant.
Also, the Nexplanon rod was designed to be located using X-rays. If you doctor can't feel it under the skin, the X-ray can help him or her see if it's been placed correctly.
Effective. Fewer than one in 1,000 women using an implant will become pregnant each year.
Easy to use. Unlike some other birth control options -- such as condoms, patches, shots, rings, and pills -- the implant does not rely on you to work effectively. You don't have to worry about using it incorrectly or remembering to replace or take frequently.
Fast reversal. You will be able to get pregnant immediately after the implant is removed, which is a benefit if you want to become pregnant.
Less painful periods. In studies of women using implants, painful periods were significantly improved.