Researchers found hormonal ntrauterine devices (IUDs) and contraceptive implants most likely remain effective at least one year beyond their expiration date.
The team investigated whether or not these contraceptive devices remain effective for up to three years past their recommended length of use as approved by the Food and Drug Administration (FDA), Washington University in St. Louis reported. Currently, contraceptive implants are approved for three year of uses, and hormonal IUDs are approved for five years.
"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 first author Dr. Colleen McNicholas, assistant professor of obstetrics and gynecology.
The study, which plans to eventually enroll 800 participants, looked at 237 women who used implants and 263 who used hormonal IUDs. The study subjects were between the ages of 18 and 45 who used contraceptives that were within six months of expirations at enrollment, they were informed of potential pregnancy risk if these methods were used past their approved dates.
The researchers did not observe any pregnancies in the implant group and only one in the hormonal IUD group, which is a similar rate of failure to what is seen in IUDs used within five years after implantation. Further observations could confirm these preliminary results and even extend them by an additional two years.
"The longer a contraceptive method is effective, the bigger the impact it can have," said senior author Jeffrey Peipert, the university's Robert J. Terry professor of obstetrics and gynecology. "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."
The preliminary results appeared Feb. 5 in the journal Obstetrics & Gynecology and will appear in the journal's March 15 print edition. The project was supported by the Society of Family Planning, the Washington University Institute of Clinical and Translational Sciences National Center for Research Resources.
