Only two forms of “next day” contraception are approved by the Food and Drug Administration, both hormonal drugs taken orally as pills: levonorgestrel (Plan B One-Step and other brands, available over-the-counter) and ulipristal acetate (Ella , available by prescription). Observational studies strongly suggest that a non-hormonal copper intrauterine device (ParaGard) may also be effective.
Now, researchers have found that another type of IUD, one containing the hormone levonorgestrel (Liletta and other brands), works as well as copper IUDs and perhaps even better than FDA-approved oral pills to prevent pregnancy.
The study, published in the New England Journal of Medicine, tested the copper IUD against intrauterine levonorgestrel in a randomized trial. The researchers recruited 638 women seeking emergency contraception at three family planning clinics in Utah, randomly assigning them to either device.
After one month, there was no pregnancy among women who used the copper IUD and one among those who used the hormonal IUD. The researchers estimate that the incidence of pregnancy with intrauterine levonorgestrel is 0.3 percent, compared with 1.4 to 2.6 percent with oral contraceptives.
None of the intrauterine devices are approved for emergency contraception, but the study’s lead author, Dr. David K. Turok, an associate professor of obstetrics and gynecology at the University of Utah, expects professional guidelines to include them soon.
“The main thing is that this is another option that can be highly attractive,” he said. “We now have a well designed and executed study that shows that it can be used.”