Overview of Contraception

The decision to begin, prevent, or interrupt a pregnancy may be influenced by many factors, including personal, medical, family, and socioeconomic factors.

Contraception can be used by people to prevent pregnancy temporarily or to provide permanent contraception (sterilization). Abortion (interruption of pregnancy) may be considered when contraception has failed or has not been used, or when issues occur during the pregnancy.

Among contraceptive users in the United States, the most commonly used methods (1) are

• Oral contraceptives (OCs): 21%

• Female permanent contraception (sterilization): 28%

• Male condoms: 13%

• Male permanent contraception: 9%

• Intrauterine devices (IUDs): 13%

• Withdrawal (coitus interruptus): 6%

• Progestin injections: 3%

• Contraceptive rings or patches: 2%

• Subdermal progestin implants: 3%

• Fertility awareness methods (periodic abstinence): 3%

• Female barrier methods: < 1%

(See table Comparison of Common Contraceptive Methods.)

Pregnancy rates tend to be higher during the first year of use of a contraceptive method and decrease in subsequent years as users become more familiar with the method. Also, as women age, fertility declines. By comparison, for fertile couples trying to conceive, the pregnancy rate is about 85% after 1 year if no contraceptive method is used.

In the first year of use, pregnancy rates with typical use are

• < 1% for methods that do not require user involvement (IUDs, subdermal progestin implants, sterilization)

• 6 to 9% (approximately) for hormonal contraceptives that require user involvement but are not related to coitus (estrogen-progestin OCs, transdermal patches, or vaginal rings; progestin-only OCs; progestin injection)

• > 10% for coitus-related methods (eg, condoms, diaphragms, fertility awareness methods, spermicides, withdrawal)

Despite the higher pregnancy rate associated with condom use, condoms (primarily latex and synthetic condoms) are highly protective against transmission of sexually transmitted infections (STIs), including HIV. As part of safer sex practices, condoms should be used even when a patient is using another birth control method.

If unprotected sex occurs, emergency contraception may help prevent an unintended pregnancy. Emergency contraception should not be used as a routine form of contraception.