How Plan B Works

What you need to know to
educate women on Plan B

Women have turned to Plan B One‑Step for years when their birth control plan A didn’t work out. Plan B is emergency contraception that helps prevent pregnancy when taken within 72 hours of unprotected sex or birth control failure. We recommend that stores carry Plan B right on the shelf so that it’s available to anyone who needs it. Regardless of where women buy it, there’s no prescription or ID needed—and no age requirement, either.

What Plan B is:

  • Progestin‑only emergency contraception that works by delaying ovulation

    Similar to birth control pills, Plan B works by delaying the release of an egg from the ovary.

  • The same active ingredient as regular birth control pills—just at a higher dose

    It’s a single tablet that contains levonorgestrel 1.5 mg, an ingredient that’s been safely used in many birth control pills for decades.

  • Won’t hurt the chances of getting pregnant later on

    While it does help prevent pregnancy after unprotected sex, it won’t affect a woman’s ability to get pregnant later on.

What Plan B isn’t:

  • Not an abortion pill

    It won’t affect or harm an existing pregnancy, as it works by delaying the release of an egg from the ovary.

  • Not regular birth control

    It’s not meant to be used as a regular birth control method.

  • Won’t protect against HIV/AIDS or other STDs

    Plan B will help prevent pregnancy before it starts, but it won’t prevent any sexually transmitted diseases. With that in mind, women should always use a barrier method, like condoms, to prevent STDs.

Did you know?

Unlike other emergency contraception options, women can and should resume their regular hormonal birth control immediately after taking Plan B.

Why? Plan B contains the same active ingredient as many popular birth control pills—levonorgestrel—just at a single, higher dose.

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