[Emergency contraception].

Abstract

Emergency contraception (EC) refers to methods usually based on standard contraceptives for use within a few days of unprotected intercourse to prevent pregnancy. The most common, used in many countries for over 2 decades, is based on high doses of combined oral contraceptives (OCs) taken within 72 hours of unprotected coitus, followed by a second dose 12 hours later. Copper IUDs inserted within 5 days also provide protection. The "morning-after pills" have no effect on a pregnancy that is already established, do not cause abortion, and have not been shown to cause congenital malformations in case of failure. Emergency OCs entail no risk for most women, and occasional use is not believed to carry the same risks as regular OC use for women at cardiovascular risk, although progestin-only EC may be indicated. Only about 2% of women who use EC become pregnant. EC is useful in case of method failure, unexpected sexual relations, or rape. EC may reduce recourse to abortion by preventing unwanted pregnancy. There is no evidence that availability of EC increases sexual activity among young people. Women are not likely to replace their regular methods with emergency OCs because of the side effects, greater expense, and lower efficacy. Adding EC to existing reproductive health services is not costly in itself and offers savings in care for unwanted pregnancy and abortion.