12 Types of Birth Control
What it's called: Implanon, Norplant
What it does: About the size of a matchstick, the implant is placed under the skin on your upper arm. Implants last for three years and can cost up to $800. They are nearly 100% effective.
Who should avoid it: Implanon may not work as well for women taking St. John's wort, or women who are overweight.
Get the latest health, fitness, anti-aging, and nutrition news, plus special offers, insights and updates from Health.com!