Plan B One-Step® is one tablet that contains levonorgestrel, a hormone that has been used in many birth control pills for several decades. Plan B One-Step® contains a higher dose of levonorgestrel than birth control pills, but works in a similar way to help prevent pregnancy.

It works mainly by:
  • Stopping the release of an egg from the ovary
It is possible that Plan B One-Step® may also work by:
  • Preventing fertilization of an egg (the uniting of sperm with the egg)
  • Preventing attachment (implantation) to the uterus (womb)

But remember, Plan B One-Step® should not be used as a regular birth control method,
because it's not as effective.

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