February 9, 2015 — Intrauterine devices and contraceptive implants that contain hormones could prevent pregnancy for at least a year beyond their FDA-approved length of use, according to early findings in an ongoing study, HealthDay/U.S. News & World Report reports.
The findings, published Thursday in Obstetrics & Gynecology, are from a continuing study examining whether hormonal long-acting reversible contraceptives could be effective for up to three years beyond their approved length of use. Currently, hormonal IUDs are approved for up to five years of use, while contraceptive implants are approved for up to three years of use.
Researchers from the Washington University School of Medicine in St. Louis plan to enroll a total of 800 women in the study. The early results are from a group of 263 women who used the Mirena hormonal IUD and 237 women who used the Implanon and Nexplanon contraceptive implants. All of the women were ages 18 through 45 and were using contraceptives that were within six months of expiring when the study started.
According to the study, none of the women in the implant group became pregnant while using the contraceptives beyond their expiration date, while one woman in the IUD group became pregnant. According to the researchers, the IUD failure rate in the study was similar to that within the approved five years of IUD use.
Researchers will continue to track the participants from the initial phase of the study, as well as the newly enrolled women.
Study first author Colleen McNicholas, an assistant professor of obstetrics and gynecology at the medical school, said the findings are "important because extended use of these devices will reduce cost to both the individual and insurer and improve convenience for women, who can delay removal and reinsertion."
Other experts noted that IUDs and implants also have the benefit of reduced menstrual bleeding for many women and that the possibility of extended use could encourage uptake of the methods, which are underutilized in the U.S. (Preidt, HealthDay/U.S. News & World Report, 2/5).