Sexual Health: Emergency Contraception

Emergency contraception -- also called postcoital contraception -- is a form of birth control that may be used by women who have had unprotected sex or if a contraceptive method fails. The treatment generally is reserved for emergency situations and is not a regular method of birth control. Emergencies include being raped, having a condom break or slip off during sex, missing two or more birth control pills during a monthly cycle, and having unplanned sex.

How Does It Work?

Emergency contraception may prevent pregnancy by temporarily blocking eggs from being produced, by stopping fertilization, or keeping a fertilized egg from becoming implanted in the uterus.

Emergency contraception can be provided in two ways: using hormonal contraceptive pills or inserting a copper-releasing IUD (intrauterine device).

• Emergency Contraceptive Pills (ECP) are most commonly used and are taken in two doses. The first dose should be taken as soon as possible within 72 hours of unprotected intercourse, and the second dose 12 hours later.
• An IUD can be inserted to prevent pregnancy within five to seven days after unprotected intercourse

How Effective Is Emergency Contraception?

The pills are 75-89% effective when taken within 72 hours of unprotected sex. An IUD can be up to 99% effective when inserted within 5 to 7 days after unprotected intercourse. The sooner you take an emergency contraceptive method, the more effective it will be at preventing pregnancy.

Where Can I Get Emergency Contraception?

ECP are available at Planned Parenthood; college, public, and women's health centers; private doctors; and some hospital emergency rooms.

Some doctors will prescribe ECP over the phone and call the prescription in to a pharmacy.

Who Should Not Use Emergency Contraception?

Emergency contraception should not be used by women who are already pregnant because it is ineffective at terminating established pregnancies.

Are There Any Side Effects Associated With Emergency Contraception?

The most common side effects associated with emergency contraception include:

• Nausea
• Abdominal pain
• Fatigue
• Headache
• Menstrual changes

Ask your doctor or pharmacist about ways to reduce nausea. They may prescribe some anti-nausea medicine for you to take before you take ECP.

Does It Protect Against Sexually Transmitted Diseases?

No. Emergency contraception will not protect you from contracting an STD, such as HIV, the virus that causes AIDS. The best way to avoid getting STDs is to limit sexual contact with one uninfected partner. If that is not an option, use a latex condom correctly every time you have sex.

Reviewed by the doctors at The Cleveland Clinic Department of Obstetrics and Gynecology.