How Plan B Works

It’s important to feel informed and in control when it comes to your sexual health and preventing pregnancy.

So let’s start with the facts. Plan B is safe and effective emergency contraception. It is not an abortion pill and will not harm an existing pregnancy.

What you should know about Plan B:

  • A backup plan you can count on after unprotected sex

    Plan B must be taken within 72 hours after one incident of unprotected sex (i.e., the condom breaking or missing a birth control pill). And the sooner you take it, the better it works.

  • Emergency contraception that works by temporarily delaying ovulation

    Similar to birth control pills, Plan B works by temporarily delaying ovulation (the release of an egg from the ovary), so there’s no egg to meet the sperm. No egg, no fertilization, no pregnancy.

  • It won’t impact your ability to get pregnant later on

    Not ready right now, but think you might want to get pregnant in the future? Plan B only temporarily delays ovulation. Taking it now to help prevent pregnancy after unprotected sex won’t impact your ability to get pregnant in the future.

How does Plan B fit into your birth control regimen?

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.

Keep in mind:

Plan B won’t interfere with your regular birth control methods or make them any less effective. So, you can continue your regular birth control right away—or start one, if you don’t have a regular method.

Still have questions?

We’ve got you covered.