Frequently Asked Questions

Plan B can significantly decrease the chance that you get pregnant. When used as directed, about 7 out of every 8 women who could have gotten pregnant did not become pregnant after taking Plan B.

Birth control (or contraception) is any method, medicine, or device used to prevent a pregnancy before it starts. There are many different types of birth control. Some work better than others at preventing pregnancy and no method is 100% effective. But your chances of getting pregnant are lower if you use a more effective method.

Primary methods of birth control are meant to be used before sex to prevent a pregnancy. These methods can range from things like condoms (which can be found right at the store without a prescription) to birth control pills or IUDs (which need to be prescribed by your doctor).

Emergency contraception (like Plan B) is a form of birth control that is meant to be used if your primary method failed (like a condom broke or you missed pills) or you forgot to use primary birth control. Plan B is used to help prevent pregnancy after sex and must be taken within 72-hours after unprotected sex or if your primary birth control failed. The sooner you take it, the better it will work. It is not meant to be used as a regular form of birth control because it is not as effective.

If you find that you are using Plan B frequently, talk to your doctor about finding a primary birth control method (a “plan A” method) that is right for you.

Here’s what we know: Regardless of weight or BMI, studies show that all women can safely use Plan B to help prevent pregnancy before it starts after unprotected sex or contraceptive failure. When it comes to efficacy, the most important factor is time — because the sooner you take Plan B after unprotected sex, the better it works. This is true no matter what you weigh. When taken as directed, within 72 hours after unprotected sex, Plan B can significantly decrease the chance of getting pregnant.

If you’ve had unprotected sex or birth control failure, it’s normal to feel anxious. We want you to feel empowered to make the best decision for yourself when choosing an option to help prevent pregnancy after unprotected sex. That’s why we believe it’s so important to know the facts about how Plan B works — so you can take action to help prevent pregnancy. In cases of contraceptive failure, regardless of your weight or BMI, using a safe emergency contraceptive like Plan B is a step you can take to help prevent pregnancy. And, taking Plan B won’t impact your future fertility, regardless of weight or BMI.

Here’s how things stand: While there has been research on this topic, the available data are not definitive, and the healthcare community maintains their recommendation of taking Plan B after unprotected sex. You should speak with your healthcare professional or pharmacist if you’re concerned about Plan B working for you. There are other options available for emergency contraceptive measures that your doctor can prescribe.

It’s important to note that emergency contraception is not meant to be used as a regular form of birth control because it’s not as effective. If you find that you’re using Plan B frequently, talk to your doctor about finding a primary birth control method that’s right for you.

Plan B One-Step works by temporarily delaying ovulation after unprotected sex or where your birth control might have failed. By delaying ovulation, it means that it delays or stops the release of an egg from the ovary, so there’s no egg to meet the sperm. No egg, no fertilization, no pregnancy.

It doesn’t stay in your system or impact your ability to become pregnant in the future.

Plan B does not impact your ability to get pregnant in the future. After temporarily delaying ovulation, you will continue to ovulate in the future, and can still get pregnant later, if you choose to.

Plan B is not an abortion pill and it will not be effective if a woman is already pregnant. Plan B will not harm an existing pregnancy.

Yes! Plan B does not impact the effectiveness of any regular birth control methods, so you can continue your regular birth control right away—or start one, if you don’t have a regular method.

The sooner you take Plan B after unprotected sex, the better it works. You must use it within 72‑hours after unprotected sex.

Plan B One‑Step is one pill that you place in your mouth and swallow, preferably with water. You can take Plan B with or without food. The most important thing to know about taking Plan B is that it must be taken within 72 hours (3 days) after unprotected sex to help prevent pregnancy before it starts. The sooner you take it, the better it works.

Yes, you can use Plan B when you are breastfeeding. In general, no harmful effects of progestin‑only pills, like Plan B, have been found on breastfeeding performance or on the health, growth, or development of the infant. However, random cases of decreased (less) milk production in mothers have been reported.

Plan B emergency contraception should not be used as a regular method of birth control. However, if you have already used Plan B, it can be safely used again after another instance of unprotected sex or birth control failure. It works in the same way every time you take it and will not become less effective over time.

Plan B doesn’t provide long‑term protection against future pregnancy—it works to help prevent pregnancy after only one act of unprotected sex or birth control failure. It will not affect your future fertility.

Plan B only stays in your body for a short amount of time. It doesn’t provide long‑term protection against future pregnancy; when taken as directed it works to help prevent pregnancy after only one incident of unprotected sex. If you are sexually active, even occasionally, see your healthcare professional or visit a family planning center/clinic to find a regular method of birth control that suits you.

Find a Family Planning Clinic

Do not take Plan B:

• If you’re already pregnant, because it won’t work
• If you’re allergic to levonorgestrel or any of the ingredients in Plan B
  In place of regular birth control
• If you’re male

This product is not intended for use in postmenopausal women.

Use before the first menstrual period is not appropriate.

When used as directed, Plan B is safe and effective.

Some women may experience side effects, including:

• a period that’s lighter, heavier, early, or late
• nausea
• lower abdominal cramps
• tiredness
• headache
• dizziness
• breast tenderness
• vomiting

Some women taking Plan B may have changes in their period, such as spotting or bleeding before their next period. If your period is more than a week late, it’s possible you might be pregnant. Get a pregnancy test and follow up with your healthcare professional.

If you vomit within 2 hours of taking Plan B, talk to your healthcare professional to find out if you should repeat the dose.

Examples of drugs or herbal products that could decrease the effectiveness of Plan B include barbiturates, bosentan, carbamazepine, felbamate, griseofulvin, oxcarbazepine, phenytoin, rifampin, St. John’s wort, topiramate, and certain HIV/AIDS medications.

Contact your healthcare professional before taking Plan B if you have any concerns or are taking any of these medications.

No. Plan B is available for purchase in every state—no prescription or ID needed. There’s also no age requirement. Anyone can buy it.

First and foremost, Plan B is an emergency contraceptive—it is not an abortion pill. Plan B has been FDA‑approved since 2013 for purchase without a prescription, ID, or age restriction. It can be found at all major retailers across the country, in every U.S. state.

The availability and access of Plan B is governed nationally by the U.S. Food and Drug Administration (FDA). Plan B is not in any way connected to Roe v Wade. Plan B will continue to be made available at all major retailers without a prescription, ID or age restriction regardless of any rulings on abortion restrictions.

Foundation Consumer Healthcare will continue to advocate that no legal barriers should limit a woman’s access to Plan B emergency contraception.

Plan B has a shelf life of four years. For the exact month and year that the Plan B is set to expire, you can refer to the information printed on the side of the box. Store the product at room temperature between 68‑ and 77‑degrees Fahrenheit.

You can find Plan B yourself in the aisle of all major retailers, including CVS, Walgreens, Rite Aid, Target, and Walmart. It’s also available at smaller pharmacies and some food stores around the country. All of the retail stores also offer ways to buy online and pickup in-store or have Plan B delivered same day.

Get Plan B

Yes. Plan B is available online in all 50 U.S. states. Buy online and pickup in-store or get same-day delivery, with one hour delivery in most cities. Find where to buy it online here.

You can save on Plan B with a coupon.

How to save

Not sure how to bring up the topic of taking Plan B? Try the tips below.

• Start with the facts. This site is full of information to help you have a conversation about Plan B—whether it’s with a friend, family member, or partner.
• Plan ahead. Consider making a list of what you want to discuss and try practicing the conversation out loud. Think about potential responses to any concerns your friend/family member/partner might have.
• Find the right time and place. Make sure you have a private place to discuss Plan B—a place where you won’t get interrupted or feel rushed.
• Be respectful. Respect what the other person is thinking and feeling. Be open to other opinions, but remember: it’s your body and your choice.
• Practice safe sex. Discuss future contraception. Safe sex is important, even if you’re in a monogamous relationship (remember: neither birth control pills nor emergency contraception like Plan B protect against STDs or HIV/AIDS).

You can find downloadable PDFs, fact sheets, and more from Plan B on our resources page.

Check out the websites below to stay informed on what’s happening in women’s healthcare, and to learn more about birth control options and emergency contraception.

• Planned Parenthood
• FDA
• American Society for Emergency Contraception
• Mayo Clinic
• Henry J. Kaiser Family Foundation
• National Family Planning & Reproductive Health Association
• Find a Family Planning Clinic
• 2026 Women’s Health Mandate

Foundation Consumer Healthcare is not responsible for the content on the websites listed above and disclaims any liability for the content of any page or site listed above.
Although the information above may be useful, it shouldn’t replace the advice of your healthcare professional. For questions about birth control and other women’s health issues, please talk to your healthcare professional.