How you prepare

By Mayo Clinic Staff

For maximum effectiveness, emergency contraception should be started as soon as possible after unprotected intercourse, and within 120 hours. You can take emergency contraceptive pills anytime during your menstrual cycle.

If you're age 17 or older, Plan B One-Step and Next Choice are available over-the-counter at most pharmacies. If you're age 16 or younger or you want to use Ella, you'll need a prescription from your health care provider. Some health care providers may provide an advance prescription for emergency contraception, just in case.

Remember to talk to your health care provider about any other medications you're taking.

Jun. 28, 2013