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Emergency contraception (or EC) is a kind of birth control you can use after an unprotected sexual encounter. You have up to 5 days after unprotected sex to use EC. EC works to prevent a pregnancy before it starts, and taking EC will not terminate an existing pregnancy. (That means it wonít work if you are already pregnant.) EC also doesnít protect against HIV or other STDs.

You may need EC in the following situations:

  • You had sex and ...
    • you didnít use anything to prevent pregnancy
    • your birth control method failed Ė like your condom broke or slipped off, or your partner didnít pull out in time
    • you are late for your Depo shot
    • you have missed doses of your birth control pill
  • You were forced to have unprotected sex

City Clinic can help you with the following options for EC:

Need a prescription for Plan B?

Which EC is right for me?

Check out this chart, made by our colleagues at Bedsider and Bixby Center at UCSF.

  • Paragard IUD is always the most effective method of EC. Paragard works over 99% of the time.
    • Paragard must be inserted by a trained healthcare provider.
    • Paragard works against pregnancy, no matter how much you weigh.
    • Paragard is as effective at 5 days as it is right after an unprotected encounter.
    • Paragard can be left in place for up to 12 years as ongoing birth control.
  • ella is the second most effective method.
    • ella is available by prescription only.
    • ella is as effective at 5 days as it is right after an unprotected encounter.
    • If you weigh more than 195 pounds, ella may not be effective at preventing pregnancy.
  • Plan B is the third most effective kind of EC.
    • Anyone can buy Plan B, regardless of age or gender.
    • You can buy plan B without a prescription Ė just ask your pharmacist for the medication.
    • Plan B can be used up to 5 days after unprotected sex, but is more effective the sooner you take it.
    • If you weigh more than 165 pounds, Plan B may not be effective against pregnancy.

Can I use regular birth control pills as EC?

Last modified on Thursday, June 15, 2017.
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