Emergency Contraception

Emergency contraceptives prevent pregnancy after unprotected sexual intercourse. It can also be used when:

  • A condom breaks.

  • After a sexual assault.

  • You forgot to take your birth control pills.

  • When inadequate protection with sexual intercourse occurs.

Usually, emergency contraception is a pill taken right after sex or up to 5 days after unprotected sex. It is most effective the sooner you take the pills after having sexual intercourse. Emergency contraceptive pills are available without a prescription. Check with your pharmacist. Do not use emergency contraception as your only form of birth control. They do not protect against sexually transmitted infections (STIs).

Emergency contraception will not work if you are already pregnant and will not harm the baby if you are pregnant. Emergency contraception does not cause an abortion. They work by preventing the ovaries from releasing an egg (ovulation) or the fertilization of an egg. Taking St. John's Wort, certain antibiotic medicines, and certain anti-convulsion medications may make these pills less effective.

Discuss with your caregiver the possible side effects of emergency contraceptives.


  • Some types of emergency contraceptive pills contain estrogen and progesterone in higher doses.

  • Some types use 2 pills with a high dose of progesterone.

  • Some types use 1 pill with a double dose of progesterone.

  • An intrauterine device (IUD) may be used. This T-shaped device is also used as a form of birth control. It is inserted into the uterus to prevent pregnancy. The copper IUD can also be used as emergency contraception if inserted within 5 days of having unprotected intercourse.


  • Eat something before taking the emergency contraceptive pills.

  • Lie down for a couple of hours if you become tired or dizzy.

  • Continue using birth control until you start your menstrual period.


  • You throw up (vomit) within 2 hours after taking the pill. You will have to take another pill.

  • You need treatment for nausea, vomiting, headache, or belly (abdominal) cramps.

  • You have not had a menstrual period 21 days after taking the pill.

  • You are having irregular bleeding or spotting.


  • You have chest pain.

  • You have leg pain.

  • You have numbness or weakness of your arms or legs.

  • You have slurred speech.

  • You have visual problems.