NEW YORK — More than 90 percent of women who opt for long-term reversible forms of birth control keep using them for at least six months, a new study found.
Those birth control methods include intrauterine devices (IUDs) and contraceptive implants.
The findings mean most women did not have side effects, such as cramping or bleeding, that were serious enough for them to stop using their birth control.
"There is the perception among health care providers that women discontinue these methods rapidly," senior author Dr. Tessa Madden said. She is an assistant professor of obstetrics and gynecology at the Washington University School of Medicine in St. Louis.
IUDs are placed inside the uterus and prevent pregnancy for up to five or 10 years, depending on the brand. The contraceptive implant is inserted under the skin of a woman's arm and works for three years.
Both methods are 99 percent effective at preventing pregnancy — better than the Pill, the vaginal ring and condoms. But they are used by less than one in 10 U.S. women.
That is partly because some doctors may assume women will not be happy with these methods, the researchers said.
"We hope that this study helps reassure providers that the discontinuation rate is not a big concern," Madden said.
Her team's study included about 6,000 women between the ages of 14 and 45. Women could choose to start using the levonorgestrel-releasing IUD (marketed as Mirena), the copper IUD (ParaGard) or the contraceptive implant (Implanon).
The researchers counseled women about what to expect with their chosen birth control method. Then they kept track of if, when and why women stopped using their birth control through phone calls.
About seven percent of women using levonorgestrel IUDs or implants and eight percent of copper IUD users chose to have their device removed in the first six months. Younger women continued using these methods just as often as older women did, according to findings published in the journal Obstetrics and Gynecology.
"We showed in this analysis that fewer than 10 percent of women discontinue before six months, and that the same is true for teens," Gina Secura said. An epidemiologist at Washington University in St. Louis, she also worked on the study.
That's important because younger women may stand to benefit most from IUDs or contraceptive implants, Madden told Reuters Health. These women tend to have more pregnancies than older women while using other types of birth control, such as the Pill or the vaginal ring.
"Many providers and clinic staff incorrectly believe that young women will quickly discontinue these (long-acting) methods because of side effects," Secura told Reuters Health. "Because of this misconception, providers and clinics are reluctant to offer long-acting reversible contraceptive methods to many young women."
This study is one of several that open the door to making implants and IUDs go-to birth control methods for all women who want them, the researchers said.
"This is a paradigm shift in family planning," Madden said.
She cited recommendations from the American Congress of Obstetricians and Gynecologists last year to offer implants and IUDs as first-line birth control methods to all women.
"Studies like this will encourage providers to use these methods more," Madden said, "and to not create additional barriers for women to get the most effective methods."