Only two forms of “morning-after” 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 a different type of IUD, one that contains the hormone levonorgestrel (Liletta and other brands) works as well as the copper IUD, and perhaps even better than the FDA-approved oral pills to prevent pregnancy.
The study, in the New England Journal of Medicine, tested the copper IUD against intrauterine levonorgestrel in a randomized trial. Researchers recruited 638 women seeking emergency care at three Utah family planning clinics, randomly assigning them to one device or another.
After one month, there were no pregnancies among women who used the copper IUD, and one among those who used the hormonal IUD. The researchers calculate that the incidence of pregnancy with intrauterine levonorgestrel is 0.3 percent, compared to 1.4 to 2.6 percent with oral contraceptives.
None of the intrauterine devices have now been 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 most important thing is that this is another option that can be very attractive,” he said. “Now we have a well-designed and conducted study that shows that it can be used.”