Effectiveness: 92 to 99 percent; it is more than 99 percent effective if used as directed (1-9 pregnancies per 100 women each year).
What is it? The ring is a thin, clear, flexible 2-inch circle that you insert anywhere in your vagina and leave for 3 weeks. It slowly releases the synthetic hormones estrogen and progestin. At the fourth week, you remove the ring and have your period, or you can leave it in to avoid having a period. At the fifth week, you insert a new ring. Brand name is NuvaRing.
How does it work? Like birth control pills, the ring releases estrogen and progestin, which 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 is simple and convenient and allows women to feel more spontaneous about having sex. It may make your periods regular, lighter and shorter. Like other hormonal forms of birth control, the ring may offer some protection against acne; severe menstrual cramps; bone thinning; ectopic pregnancy; endometrial and ovarian cancers; iron deficiency anemia; serious infections in the ovaries, fallopian tubes and uterus; breast and ovarian cysts; pelvic inflammatory disease; and premenstrual symptoms. Your ability to get pregnant returns quickly when you stop using the ring.
Disadvantages: For the first couple of months, it may cause bleeding between periods, nausea and vomiting and breast tenderness. Other side effects may include vaginal irritation, infection or discharge; weight changes; water retention; increased blood pressure; mood changes; abdominal cramps; difficulty wearing contact lenses; rash; spotty darkening of the skin; or headaches. Rarely, the ring may fall out when you remove a tampon, go to the bathroom or have sex. If it falls out, rinse with warm water and put it back in your vagina within 3 hours. As with other forms of hormonal birth control, there is a slightly increased risk of heart attack, stroke and blood clots. The ring is not recommended if you are pregnant; are over 35 and smoke; or have certain other health conditions (see Notes below). Certain medicines and supplements may make the patch 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. Serious complications are rare, but always talk with your health care provider about risks and benefits.
Availability: Prescription required.
Cost: $15 to $80 a month.*
Notes: One size fits all. Neither you nor your partner is likely to feel the ring. The ring is not recommended for use during prolonged bed rest or if you are pregnant; have migraine headaches with aura; have blood clots or vein problems; have (or have had) cancer of breast, reproductive organs or liver; have had a heart attack, stroke or angina; have had serious heart valve problems; have certain hereditary blood-clotting disorders; have unexplained vaginal bleeding; have serious diabetes or liver disease; have uncontrolled high blood pressure or high cholesterol and triglycerides; have an allergy or sensitivity to the components of the ring; are 35 or older and smoke; or have high blood pressure and smoke. Women who use hormonal contraception are strongly advised not to smoke.
* 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.