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Overview of Contraception


Frances E. Casey

, MD, MPH, Virginia Commonwealth University Medical Center

Last full review/revision May 2020| Content last modified May 2020
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A couple’s decision to begin, prevent, or interrupt a pregnancy may be influenced by many factors including maternal medical disorders, risks involved in the pregnancy, and socioeconomic factors.

Contraception can be used by one or both members of a couple to prevent pregnancy temporarily. Some procedures are intended to provide permanent contraception (sterilization). Abortion (termination of pregnancy) may be considered when contraception has failed or not been used.

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

  • Oral contraceptives (OCs): 19%

  • Female permanent contraception (sterilization): 29%

  • Male condoms: 13%

  • Male permanent contraception: 9%

  • Intrauterine devices (IUDs): 12%

  • Withdrawal (coitus interruptus): 6%

  • Progestin injections: 3%

  • Contraceptive rings or patches: 2%

  • Subdermal progestin implants: 4%

  • Fertility awareness methods (periodic abstinence): 2%

  • Female barrier methods: < 1%

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

  • < 1% with methods unrelated to coitus and not requiring user involvement (IUDs, subdermal progestin implants, permanent contraception)

  • About 6 to 9% with hormonal contraceptive methods unrelated to coitus and requiring user involvement (oral contraceptives, progestin injection, transdermal patch, vaginal ring)

  • > 10% with coitus-related methods requiring user involvement (eg, condoms, diaphragms, fertility awareness methods, spermicides, withdrawal)

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

Despite the higher pregnancy rate associated with condom use, experts recommend that condoms always be worn during intercourse because condoms (primarily latex and synthetic condoms) protect against sexually transmitted diseases (STDs). Most importantly, they help protect against HIV. For most effective contraception, other birth control methods should be used with condoms.

If contraception fails, emergency contraception may help prevent an unintended pregnancy. Emergency contraception should not be used as a regular form of contraception.


Comparison of Common Contraceptive Methods


Pregnancy Rate in First Year of Use With Perfect Use

Pregnancy Rate in First Year of Use With Typical Use

Percentage of Women Continuing Use at 1 Year

Requirements for Use

Selected Disadvantages


Levonorgestrel-releasing intrauterine devices (IUDs)

0.3–0.5% (3-year IUD) or 0.2% (5-year IUD)

Same as perfect use


Insertion every 3 years or 5–6 years (depending on type)

Spontaneous expulsion, uterine perforation (rare)

Irregular bleeding, amenorrhea




Pill taken daily

Progestin-only pills: Taken at the same time every day

Fluid retention, irregular bleeding, breast tenderness, nausea and vomiting, headache, weight gain, multiple drug interactions

Combination OCs: Increased risk of venous thromboembolism

Progestin-only OCs: Similar to those of contraceptive implants




Injection every 3 months

Amenorrhea, irregular bleeding, weight gain, headache




Implant every 3 years (some evidence supports ovulation suppression to 5 years)

Amenorrhea, irregular bleeding, headache, weight gain




Weekly application and removal

Similar to OCs

Local irritation




Monthly application (inserted vaginally) and removal

Similar to OCs


8% (higher among parous women)


Must be used with each coital act

3 sizes (size chosen based on the woman's pregnancy history)

Should be left in the vagina for ≥ 6 hours after intercourse

Possibly vaginal irritation or ulceration if left in place for > 48 hours

Condom, male†




Must be used with each coital act

Requires cooperative partner

Allergic reactions

Condom, female†




Must be used with each coital act

Allergic reactions

(containing sustained-release spermicide)

9% for nulliparous women

20% for parous women

12% for nulliparous women

24% for parous women


Must be used with each coital act

May be inserted 24 hours before intercourse

Must remain in place for ≥ 6 hours after intercourse

Allergic reactions, vaginal dryness or irritation

Diaphragm with spermicide




Must be used with each coital act

Must be inserted ≤ 6 hours before intercourse

May be left in place 6–24 hours after intercourse

Occasionally vaginal irritation

Increased incidence of urinary tract infections (UTIs)


Copper-bearing T380A IUDs


Same as perfect use


Insertion every 10 years

Spontaneous expulsion, uterine perforation (rare)

Increased menstrual blood loss, pelvic pain

Fertility awareness–based methods (periodic abstinence)

4% or higher, depending on method



Training, effort, and multiple steps required for the more effective methods

No likely systemic or significant local adverse effects

Withdrawal method




Must be used with each coital act

Requires cooperative partner

Permanent contraception (sterilization)


Same as perfect use


Requires a procedure (typically done in an operating room)

Considered permanent


Same as perfect use


Requires a procedure (done in an office) and a local anesthetic

Considered permanent

* Oral contraceptives (OCs) have health benefits other than contraception.

† Condoms, primarily latex and synthetic condoms, protect both partners against sexually transmitted diseases.

N/A = not applicable.

Data based on Association of Reproductive Health Professionals: Choosing a Birth Control Method. 2014. This organization has ceased operations.

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