A recent study reveals hormonal intrauterine devices (IUDs) are safe and effective as emergency contraception.

  • Hormonal IUDs are more effective at preventing pregnancy than the Plan B levonorgestrel emergency contraceptive pill, and they provide a long-term contraception solution.
  • The copper IUD already was shown to be an effective form of emergency contraception. Now, the new research opens the path for providers to prescribe the hormonal IUD for the same purpose.
  • Another positive finding is that the hormonal IUD can be placed safely at any point in a patient’s menstrual cycle (following a negative pregnancy test).

When patients seek an emergency contraceptive option, some will select the copper intrauterine device (IUD) over the Plan B levonorgestrel emergency contraception pill because of the IUD’s greater efficacy and long-term contraceptive benefit.

But, until now, clinicians would not have recommended a hormonal IUD for that purpose. This may change in 2021, as more physicians follow the evidence from a recent study that shows the levonorgestrel IUD is noninferior to the copper IUD for emergency contraception.1

For people who need emergency contraception and also seek a highly effective, ongoing contraceptive, this research suggests the hormonal IUD is a good option, says Krishna Upadhya, MD, MPH, vice president of quality care and health equity with Planned Parenthood Federation of America.

“This is significant because many people might prefer the hormonal IUD. Having that as a clear option for emergency contraception is really beneficial,” Upadhya explains. “That’s the main takeaway, and it’s something that many of our health centers are eager to put into practice.”

IUD Advantages

IUDs as emergency contraception have a couple of advantages over Plan B: They are more effective at preventing pregnancy, and they provide a long-term contraception solution. More than a decade of research shows that Plan B does not reduce rates of unintended pregnancy.2,3

“Studies show that oral emergency contraception has no effect on unintended pregnancy,” says David K. Turok, MD, MPH, lead author of the study and associate professor in the department of obstetrics and gynecology at the University of Utah.

Estimates suggested that Plan B would lead to a 50% drop in unintended pregnancy and abortion rates, but this never happened. Researchers found that the copper IUD is much more effective than oral emergency contraceptives at preventing both fertilization and implantation.2

Surprised that emergency contraception did not solve this problem, Turok and other researchers decided to investigate the use of an alternative to the Plan B pill: a hormonal IUD.

“In our current study, people came to the clinic, requesting emergency contraception. [If they enrolled in the study] they were randomized to get either the copper or hormonal IUD,” Turok explains.

This IUD research took place in the past decade when IUD use was increasing in the United States. By 2014, IUDs comprised almost 12% of overall contraceptive use among people in the United States,4 says Elizabeth Watkins, PhD, dean of the graduate division, vice chancellor of student academic affairs, and professor of history of health sciences at the University of California, San Francisco. (See story on the history of IUDs in this issue.)

Between 2008 and 2014, the largest increase in contraceptive use was among people who used long-acting, reversible contraceptive (LARC) methods, including the IUD.4-6

“First, we looked at emergency contraceptive vs. copper IUD. Second, we had people select a copper IUD or levonorgestrel IUD, and if they got the hormonal IUD, they also took Plan B,” Turok explains. “The third study compared the copper IUD and hormonal IUD.”

More people wanted the hormonal IUD, and the pregnancy rates were lower than expected. “The point of doing this current study was to show you didn’t also need Plan B,” Turok says.

While IUDs do not work for all people, they are a good option for patients interested in using a quick-start contraceptive. A family planning clinic can provide patients with an IUD on the day they walk into the clinic, Turok says.

Many physicians will not place a hormonal IUD on the same day of the patient’s walk-in visit if the patient says she has just had unprotected intercourse. “These data say you can place it, and you can do it with confidence,” he adds.

Physicians concerned about same-day IUD placement worry about a pregnancy that is so early that placing an IUD would interfere. “In the study, we got a urine pregnancy test on everyone before the IUD was placed to make sure it was negative. If you do that, the risk going forward is very low,” Turok explains.

Participants, recruited from six Utah clinics, had at least one episode of unprotected intercourse within five days before presenting at the clinic. They agreed to a placement of an IUD, and were followed to see if pregnancies occurred within one month of IUD insertion.

There was a pregnancy rate of one in 317 in those enrolled in the levonorgestrel IUD group; in the copper IUD group, the pregnancy rates was zero in 321. Adverse events in the first month after placement amounted to 5.2% for the levonorgestrel IUD group, and 4.9% of the copper IUD group.1

“People are currently offering the copper IUD as emergency contraception, but it’s definitely being underutilized, and an even smaller group is offering levonorgestrel IUD with Plan B,” Turok says. “But this will raise awareness of both options.”

Menstrual Cycle Should Not Be a Barrier

The study results also reveal that menstrual cycle timing should not be a barrier to starting the IUD. “Historically, there have been a lot of barriers to starting contraceptive methods, and it’s been around timing of menstrual cycles because providers know women are unlikely to be at risk for pregnancy if they’re menstruating, so they do an IUD insertion at that time,” says Lori M. Gawron, MD, MPH, FACOG, study co-author and associate professor of obstetrics and gynecology at the University of Utah. “That’s a barrier, too. Accessing care and scheduling care puts them at risk until they can get in and have that IUD placed.”

The study results alleviated providers’ concerns about when to place an IUD because it reinforced the idea that as long as a pregnancy test is negative, it does not matter where a woman is in her menstrual cycle, Gawron adds.

Family planning clinics likely will be the first places to change emergency contraceptive policies because of the researchers’ findings. Individual physician offices might not be able to provide same-day IUD insertion, whereas some family planning clinics can offer IUDs to women who walk in that day.

“Family planning clinics are set up for more walk-in, same-day availability,” Gawron explains. “Women can walk in for whatever they need, and there are providers on hand who can always insert IUDs.”

The finding that the hormonal IUD works as well as the copper IUD for emergency contraception means more American women may be open to that solution to prevent an unintended pregnancy.

Globally, the copper IUD is more widely used. But in the United States, more women prefer the hormonal IUD for the benefit of less bleeding, Gawron notes.

“We already knew the copper IUD works better than oral emergency contraception,” she adds. “Now, we know the hormonal IUD is equivalent to the copper one.” If a woman enters a doctor’s office or clinic and wants the best chance of preventing pregnancy, then the IUD is the best option, she says.

Policy Changes Pending

The fact that the study was published in the New England Journal of Medicine suggests it could soon lead to changes in clinical practice regarding emergency contraception, Turok says.

“This study comes from a single Planned Parenthood affiliate, and it’s very much a local study, answering a local question that has national and global implications,” he explains. “The data are going to be used all over the place, hopefully.”

Planned Parenthood Federation of America has not yet changed its standards to state that a hormonal IUD could be quick-started at any point in the cycle, or that the hormonal IUD could be a good option for an emergency contraceptive.

“That’s something we’re reviewing in terms of our guidelines,” Upadhya says. “The fact that being able to initiate an IUD at any point in the cycle would be an advantage.”

Planned Parenthood guidelines go through a standard review process before they are updated. “A complete update goes through the guidelines every couple of years,” Upadhya says. “We review data as it comes out and make changes to practices as needed.”

The new study’s findings are huge and exciting. “There are a lot of people for whom the hormonal IUD is a preferred method of birth control, and having that as an option equal to the copper IUD is a great thing for people,” Upadhya says.

“We encourage our affiliates to let us know if this is something they want to implement, and we review with them the parameters of how to do it,” she adds. “Most of our affiliates have indicated this is something they want to move forward with.”


  1. Turok DK, Gero A, Simmons RG, et al. Levonorgesterel vs. copper intrauterine devices for emergency contraception. N Engl J Med 2021;384:335-344.
  2. Michie L, Cameron ST. Emergency contraception and impact on abortion rates. Best Pract Res Clin Obstet Gynaecol 2020;63:111-119.
  3. Payakachat N, Ragland D, Houston C. Impact of emergency contraception status on unintended pregnancy: Observational data from a women’s health practice. Pharm Pract (Granada) 2010;8:173-178.
  4. Guttmacher Institute. Contraceptive use in the United States. April 2020. https://www.guttmacher.org/fact-sheet/contraceptive-use-united-states
  5. Kavanaugh ML, Jerman J. Contraceptive method use in the United States: Trends and characteristics between 2008, 2012, and 2014. Contraception 2018;97:14-21.
  6. Hubaher D, Kavanaugh M. Historical record-setting trends in IUD use in the United States. Contraception 2018;98:467-470.