The American College of Obstetricians and Gynecologists (ACOG) said long-acting reversible contraceptive methods are the most effective forms of reversible contraception available and are safe for use by almost all reproductive-age women. ACOG named the birth control implant as one of those methods.
The birth control implant is a thin rod – made of flexible plastic – about the size of a cardboard matchstick. According to ACOG, a trained health care provider inserts the implant just under the skin of the arm with a special applicator. It takes less than one minute.
A Contraception.About.com article reported the implant continually releases a low dose of etonogestrel which is a progestin to protect against pregnancy for up to three years. After the third year, it still releases some hormone, but not enough to prevent pregnancy. The implant has no estrogen, so it’s good for women who can’t tolerate it.
The implant can be removed any time before the three years are up. It does, however, need to be taken out by a health care provider. During removal, a new implant may be inserted or if a woman chooses to get pregnant, fertility usually returns in a few days.
The implant’s effectiveness decreases when used with St. John’s wort, rifampin (an antibiotic), certain oral medicines for yeast infections and some HIV and anti-seizure medications.
Beyond the implant’s effectiveness, there are other advantages. It can be used while breastfeeding. Contraception.About.com said due to the low and steady hormone delivery, the implant has fewer hormonal ups and downs than daily or weekly birth control methods.
There are also disadvantages and possible side effects. It doesn’t protect against sexually transmitted diseases.
ACOG said the most common side effect is irregular bleeding. Menstrual periods may be heavier or lighter. They may last longer, or they may be infrequent. Bleeding between periods may occur. In about 30–40 percent of women, bleeding stops completely.
Besides irregular bleeding, the most frequent side effects reported are mood swings, weight gain, breast tenderness, headache, acne, and depression.