Hormonal intrauterine devices (IUDs) and implants are effective in preventing pregnancy at least 1 year beyond the current FDA-approved duration, researchers from Washington University School of Medicine in St Louis reported.
These findings are the preliminary results of a study evaluating whether such long-acting forms of contraception are effective for up to three years past their recommended length of use per their FDA approval.
- Preliminary data suggests that hormonal IUDs and implants remain effective at least 1 year beyond their FDA-approved duration of use.
- This ongoing study aims to determine
the effectiveness of these long-term contraceptive devices for up to 3 years past their approved duration of use.
The study has included 237 women willing to continue use of their etonogestrel implant and 263 women willing to continue use of a 52-mg levonorgestrel IUD beyond the FDA-approved duration of 3 and 5 years, respectively.
Zero pregnancies have been documented in women using the etonogestrel implant for an extended time. Thirty-four women used it for 5 years, and 123 women used it for 4 years, reported the study authors in Obstetrics & Gynecology.
Among 263 levonorgestrel IUD users, one pregnancy was confirmed, for a failure rate of 0.51 (95% CI, 0.01-2.82) per 100 women-years.
The researchers also reported that serum etonogestrel levels indicate the implant contains adequate hormone for ovulation suppression at the end of both 3 and 4 years of use.
"This research is 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 re-insertion," said author Colleen McNicholas, DO, assistant professor of obstetrics and gynecology at Washington University School of Medicine St. Louis, in a news release.
These preliminary findings confirm what other European studies have shown. The aim of the study is to enroll 800 women and evaluate the effectiveness of hormonal implants and IUDs for up to 3 years beyond their approved duration of use.
"The longer a contraceptive method is effective, the bigger the impact it can have," said senior author Jeffrey Peipert, MD, PhD, the Robert J. Terry Professor of Obstetrics and Gynecology, in a news release. "In the long term, this work has the potential to change how we provide contraceptive methods around the world and can enable women to control their reproductive health and family size."