Emergency contraception probably isn’t something you think about every day, but when you do need it, it can provide a real sense of security. Even just knowing the morning-after pill is available can help you breathe easier and enjoy sex free of worry. But if you find yourself regularly relying on emergency contraception to avoid pregnancy, you might be wondering how often you can take Plan B safely. Does its effectiveness change with regular use, and does it have any long-term side effects?
The term “emergency contraception” implies that this method isn’t meant to be used routinely, but is intended for, well, emergency situations. That being said, you can’t predict when the condom will break or you’ll get behind on your birth control pills — no one is perfect, and despite your best intentions, you may sometimes end up having unprotected sex. That’s where the morning-after pill comes in. Plan B, Preventeza, and other over-the-counter emergency contraceptives can be taken up to 72 hours after unprotected sex to prevent pregnancy. They work by blocking ovulation, which means your ovary won’t release an egg to be fertilized by a sperm. They do not terminate an already existing pregnancy, so despite any misconceptions you may have heard, Plan B is not an abortion pill.
But can you rely on Plan B if you have unprotected sex several times over the course of one menstrual cycle? In terms of safety, you’ve got nothing to worry about. “If you have already used Plan B (even in the same cycle), it can be safely used again after another instance of unprotected sex or birth control failure,” Tara Evans, Marketing Director for Foundation Consumer Healthcare (Plan B’s parent company) tells Elite Daily. “But, Plan B should only be taken when your primary, regular birth control method was missed or your birth control method failed.”
Plan B is not meant to be used as a primary birth control method because "it isn’t as effective as using a regular birth control method consistently and correctly," says Evans. Whereas the birth control pill is 91% effective on average, and the IUD is more than 99% effective, Plan B is about 75-89% effective (depending on how soon you take it after unprotected sex). “Also, it is important to know that Plan B will not provide any protection against sexually transmitted diseases,” Evans notes. Not to mention, emergency contraception is expensive, coming in at about $40 to $50 for a single dose at most drugstores. There’s also a prescription version called ella, which is 85% effective when taken up to five days after unprotected sex. It's covered under many insurance plans, but getting your hands on it does require a trip to the doctor.
Elite Daily spoke with three medical professionals about whether there’s a recommended limit to how often it's medically safe to use the morning-after pill. Dr. Alyssa Dweck, OB/GYN, explains that Plan B is safe to use frequently, but says it’s not the most reliable contraceptive option. “While it's safe to take Plan B multiple times from a medical standpoint, the likelihood of failure (pregnancy) goes up the more often it’s taken; this is simply statistics,” she says. “It’s not unsafe, but it’s suboptimal since there is up to a 25% failure rate.” Technically, the likelihood you'll get pregnant after taking Plan B is the same every single time you take the pill. But since it has a relatively high failure rate, your chances of becoming pregnant increase the more often you rely on it exclusively.
If you’re looking for a more dependable contraceptive option that can be used right after unprotected sex, Dweck points to the non-hormonal copper IUD. “The copper IUD is a great post-coital contraception choice since it can provide long-lasting reversible contraception,” she says. The copper IUD can be inserted within five days of unprotected sex, and it lowers your chance of pregnancy by more than 99%. Plus, it’s effective for up to 12 years after insertion. Talk with your doctor if you have questions about whether an IUD is the right choice for you.
Dr. Lauren Streicher, Associate Clinical Professor of Obstetrics and Gynecology at the Feinberg School of Medicine, agrees that while you should absolutely use Plan B whenever you need it, relying on it regularly isn't ideal. “There are better methods of contraception on an ongoing basis, and clearly if someone needs emergency contraception that often, then they need reliable contraception,” she says. If your main contraceptive method is regularly failing you, you might need to find an option that works better for your lifestyle. For instance, if you always forget to take your pill, consider a method that you don’t have to think about every day. If the condom breaks frequently, you might not be using it correctly.
Current research suggests Plan B is not as effective for people with higher BMIs. A 2016 review of four studies in the Contraception journal found that women with BMIs of 30 or higher were four times more likely to get pregnant after using Plan B or other pills containing levonorgestrel. A 2011 study found that prescription ulipristal acetate (pills like ella) is slightly more effective for people with higher BMIs, but Planned Parenthood of Michigan warns it's not effective for people with a BMI of 35 or higher. The copper IUD is 99% effective for everyone, regardless of BMI.
When asked whether BMI plays a role in Plan B's effectiveness, Foundation Consumer Healthcare told Elite Daily there are "no safety concerns that preclude the use of levonorgestrel emergency contraceptives in women generally, and that all women, regardless of how much they weigh, can use these products to prevent unintended pregnancy following unprotected sex or contraceptive failure." This is the same stance taken by the FDA. However, Dweck agrees with the research that indicates BMI plays a role in Plan B's effectiveness, saying, "The best post-coital contraception in those with very high BMI is the copper IUD. With that said, Plan B is better than nothing for those who are in this category, but might be less effective."
One other downside to the morning-after pill is that it may come with unpleasant side effects, including irregular bleeding, cramps, and nausea. “The more you use it, you’re going to have potentially irregular bleeding and irregular cycles,” Streicher explains. “So it doesn’t make a whole lot of sense to use it as your [main] form of contraception.” While these side effects aren’t doing any damage to your body, they’re not fun to deal with when you can avoid it.
As for the long-term repercussions of using Plan B more than once in a cycle, you don’t need to stress. “There are no long-term effects on your hormones or your fertility,” Dr. Tristan Emily Bickman, OB/GYN, tells Elite Daily. While taking Plan B may alter your hormone levels during your current cycle, they will even out again within a few weeks. “If you take emergency contraception five times in one month, it’s not going to keep you from getting pregnant five years later,” says Streicher. “Certainly it’s going to impact what’s going on hormonally through that cycle, but there’s no reason to believe that, long-term, it’s going to create a problem.”
If unforeseen circumstances lead you to have unprotected sex several times in one month, take the morning-after pill as often as you need it. But you might want to reexamine the root of the problem, which is that your primary birth control method isn’t working for you. And that’s something worth talking to your doctor about, for the sake of your wallet, your physical comfort, and your peace of mind.
Dr. Alyssa Dweck, OB/GYN
Dr. Lauren Streicher, OB/GYN
Dr. Tristan Emily Bickman, OB/GYN
Tara Evans, Marketing Director for Foundation Consumer Healthcare