May 26, 2011 — Summary of "Continuation and Satisfaction of Reversible Contraception," Peipert et al., Obstetrics & Gynecology, May 2011.
According to the most recent National Survey of Family Growth, 28% of women using contraceptive methods take oral contraceptive pills, which have continuation rates as low as 29% after six months. Despite the proven safety, effectiveness and affordability of long-acting reversible contraceptive methods, intrauterine devices and subdermal implants are not as widely used in the U.S. For example, only about 5.5% of contraceptive users ages 15 through 44 use an IUD. Researchers from the division of clinical research in the Department of Obstetrics and Gynecology at Washington University in St. Louis explained that the reasons for low use of these methods include less knowledge among providers and patients, myths and misconceptions regarding side effects, high initial costs and provider biases.
The researchers devised a study to compare continuation and satisfaction rates among women using IUDs with women taking oral contraceptives. They used data on women enrolled in the Contraceptive CHOICE Project, a university-sponsored observational cohort study focused on promoting the use of long-acting reversible contraception to St. Louis-area women.
Researchers aimed to remove both financial and educational barriers to IUDs and subdermal implants. Participants in the study were recruited from St. Louis city and county clinics, as well as the university. All participants were ages 14 through 45 years old, were not using or willing to use long-term reversible contraception at the time of starting the study, did not want to conceive for at least 12 months, and were sexually active with a male partner.
The participants received standardized contraceptive counseling, which taught them about the side effects, risks and benefits of various types of contraception. Each participant was given reversible contraception at no cost for three years, during which time the researchers conducted telephone interviews at three, six, 12, 18, 24, 30 and 36 months after enrollment.
About 3,016 women (72.4%) still used their baseline method at 12 months, 996 women (23.9%) had discontinued use at 12 months and 155 women (3.7%) did not follow up at 12 months.
More than two-thirds (68.3%) who enrolled in the study chose a long-acting reversible contraceptive method, 45% chose the levonorgestrel intrauterine system, 10% chose a copper IUD and 13% chose the etonogestrel subdermal implant. About 11% of participants chose oral contraceptive pills, 10% chose the vaginal ring, 2% chose a transdermal patch and 8% chose depot medroxyprogesterone acetate (DMPA).
Continuation rates for long-acting reversible contraceptive methods ranged from 83% to 88%, the study found. At one year, continuation rates were 88% for the levonorgestrel IUS, 84% for the copper IUD and 83% for the implant. Continuation rates for the other forms of contraception were 57% for DMPA, 55% for pills, 54% for the ring and 49% for the patch. The researchers found no significant differences in continuation rates for these non-long-acting reversible methods.
About 13.8% of long-acting reversible contraceptive users discontinued use at 12 months, compared with 45.3% for other contraceptive method users. Women taking pills had significantly higher rates of discontinuation than users of IUDs or implants. Fourteen percent of copper IUD users and 5% of levonorgestrel IUD users reported terminating use of the IUD at 12 months, compared with about 45% of pill users.
Satisfaction among IUD users was the highest, with more than 80% of women indicating that they were satisfied with the method and between 66% and 70% reporting being very satisfied. About 79% of implant users were satisfied and 55% were very satisfied. The study found that satisfaction was higher (84%) among users of long-acting methods than with other methods (53%).
About six million pregnancies occur in the U.S. annually, of which approximately half are unintended. Most of these pregnancies occur when a contraceptive method is used incorrectly or inconsistently, a failure that could be reduced if clinicians were to offer "the most effective methods of contraception to women as first-line options," the researchers wrote. "Long-acting reversible contraceptive methods, including the IUD and the subdermal implant, are the most effective methods, forgettable and not user-dependent," making their "'typical use' effectiveness ... almost equal to 'ideal' effectiveness," according to the researchers.
"[W]e found that long-acting reversible contraceptive methods have the highest continuation rates and highest levels of satisfaction," the researchers wrote, adding that "both IUDs are highly effective and well tolerated." In addition, the methods ensure better continuation rates, particularly by removing some of the causes of lapses in continuation, the researchers added. Such lapses "may be caused by switching between methods or temporary discontinuation owing to an expired prescription, difficulty getting to the pharmacy or health care provider, method dissatisfaction, or side effects," the study explained.
"In conclusion, long-acting reversible contraceptive methods have the highest rates of user satisfaction and continuation of all reversible contraceptive methods. Because they are also the most effective reversible methods of contraception, they should be the methods of choice (first-line option) for women trying to avoid an unintended pregnancy," the researchers stated.