Hormonal intrauterine devices (IUDs) and contraceptive implants are garnering renewed attention in the United States because of their superior effectiveness over other forms of birth control, such as pills and condoms. And now, preliminary results of a new study at Washington University School of Medicine indicate that long-acting contraceptive methods remain highly effective one year beyond their approved duration of use.
As part of the ongoing study, the researchers are evaluating whether IUDs and implants are effective for up to three years past their recommended length of use as approved by the Food and Drug Administration (FDA). Contraceptive implants are approved for three years, and hormonal IUDs are approved for five years. Earlier studies conducted by the World Health Organization and European researchers have shown that IUDs and implants may be effective for longer periods of time.
“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,” says obstetrician and gynecologist Colleen McNicholas, DO, MSCI, the study’s first author.
Researchers evaluated the hormonal IUD Mirena and contraceptive implants Implanon and Nexplanon. Aiming for a total enrollment of 800 women, the study’s initial analysis included 237 women who used implants and 263 women who used hormonal IUDs. Participants were 18 to 45 years old, and their contraceptives had to be within six months of expiring when they enrolled. The women were informed of a possible risk of pregnancy if the devices were used beyond the time periods approved by the FDA.
The study documented no pregnancies in the implant group and one pregnancy in the IUD group. This failure rate is similar to that of IUDs used within the recommended five-year window of time. The researchers will continue to follow these women and others who enroll in the study. Final results will determine if contractive IUDs and implants are effective for up to three years beyond FDA-approved duration of use.
“The longer a contraceptive method is effective, the bigger the impact it can have,” says senior author Jeffrey Peipert, MD, MPH, MHA, PhD. “In the long term, this work has the potential to change how we provide contraceptive methods around the world and can enable women to better control their reproductive health and family size.”
Read the study online in Obstetrics & Gynecology.