Effectiveness: More than 99 percent effective (less than 1 pregnancy per 100 women each year). Effectiveness has not been tested on extremely overweight or obese women.
What is it? A flexible plastic rod, about the size of a cardboard matchstick, is inserted by a clinician under the skin of your upper inner arm. It slowly releases progestin, a synthetic version the body's hormone progesterone. Implanon lasts 3 years but can be removed by your clinician at any time.
How does it work? Like birth control pills, it uses hormones to prevent the ovaries from releasing an egg. It also prevents fertilization by affecting the lining of uterus and thickening the cervical mucus.
STD protection: No; you will still need to use condoms if you are concerned about STDs.
Benefits: It gives long-lasting birth control, which allows you to feel more spontaneous about having sex. You don't have to remember to use daily birth control or to interrupt foreplay to use birth control. It can be used if you are breastfeeding or cannot take estrogen. The rod usually is not visible. Your periods are likely to become lighter and fewer, and about one-third of implant users stop having periods after a year.
Disadvantages: You may experience irregular bleeding; many women have continual light spotting. A few women have longer, heavier periods. You may have pain or possibly an infection at the site where the implant is inserted or removed, and some women will have discoloring or scarring at the site. Other less common side effects include change in sex drive, mood swings, headache, nausea and sore breasts. It is not recommended if you are pregnant or have breast cancer. As with other forms of hormonal birth control, there is a slightly increased risk of heart attack, stroke and blood clots. Certain medicines and supplements may make the implant less effective, including the antibiotic rifampin, certain oral medicines taken for yeast infections, some HIV medicines, some anti-seizure medicines and St. John's wort. In some cases removal of the rod may be difficult and require surgery if rod breaks or becomes embedded too deeply, but this is unlikely if you choose a health care provider who is specially trained in inserting and removing the implant. Serious complications are rare, but always talk with your health care provider about risks and benefits.
Availability: Requires visits to your health care provider for insertion and removal.
Cost: $400 to $800; lasts 3 years.*
Notes: All women should consider not smoking when using hormonal birth control. The rod is usually inserted within the first 5 days of your menstrual cycle because you should not be pregnant when it's inserted. It is not reliable birth control after it has been in for 3 years.
* The Affordable Care Act requires insurance companies to cover contraceptives with no co-pay, as of August 1, 2012. Not all plans must provide immediate coverage, but as more health plans come under the law's reach, more women will have access to all free FDA-approved forms of contraception. The specifics of how and when insurance companies must comply are still being worked out. For example, insurance companies may be able to charge a co-pay for a brand name drug when a generic is available, and regulations are still being determined for contraceptive methods that involve surgery or other medical procedures. For more information, see What You Need to Know About Birth Control Coverage.