Emergency birth control
By Mayo Clinic staffEmergency birth control is a method of preventing pregnancy used after a contraceptive method fails or after unprotected sex. It prevents pregnancy by inhibiting ovulation, fertilization or implantation.
Two types of emergency birth control are available:
- Emergency contraceptive pills (ECPs)
- Intrauterine device (IUD)
A number of oral contraceptives can be used for emergency contraception in the United States, but Plan B is the only FDA-approved product specifically marketed for such purposes.
Plan B. The first Plan B tablet is taken as soon as possible within three days of intercourse, and the second tablet must be taken 12 hours later. When taken properly, Plan B is effective at preventing pregnancy. On average, eight out of 100 women who have unprotected sex during the fertile part of their cycles will become pregnant. But only one to two women out of 100 will become pregnant after taking Plan B. Occasional side effects include nausea, abdominal pain, fatigue, headache and menstrual changes. Plan B is available to women and girls age 17 and older without a prescription at most pharmacies. You must show proof of age to purchase Plan B. For girls age 16 and younger, Plan B is available only with a doctor's prescription.
Copper IUD. The copper IUD (ParaGard) is another method of emergency contraception. The device must be inserted within five days of unprotected sex. The effectiveness rate is 99 percent after insertion. That means that one out of 100 women using ParaGard may get pregnant. The IUD can be removed after a woman's next menstrual period or left in place for up to 10 years as a continual birth control system.
