Efficacy rates in this chart are based on Contraceptive Technology (17th edition, 1998). They are yearly estimates of effectiveness in typical use, which refers to a method's reliability in real life, when people don't always use a method properly. For comparison, about 85 percent of sexually active women using no contraception would be expected to become pregnant in a year.
This chart is a summary; it is not intended to be used alone. All product labeling should be followed carefully, and a health-care professional should be consulted for some methods.
Male Latex Condom
Estimated Effectiveness: 86% (a)
Some Risks (c): Irritation and allergic reactions (less likely with polyurethane)
Protection from Sexually Transmitted Diseases (STDs): Except for abstinence, latex condoms are the best protection against STDs, including herpes and AIDS.
Convenience: Applied immediately before intercourse; used only once and discarded.
Availability: Nonprescription
Female Condom
Estimated Effectiveness: 79%
Some Risks (c): Irritation and allergic reactions
Protection from Sexually Transmitted Diseases (STDs): May give some STD protection.
Convenience: Applied immediately before intercourse; used only once and discarded.
Availability: Nonprescription
Diaphragm with Spermicide
Estimated Effectiveness: 80%
Some Risks (c): Irritation and allergic reactions, urinary tract infection
Protection from Sexually Transmitted Diseases (STDs): Protects against cervical infection; spermicide may give some protection against chlamydia and gonorrhea; otherwise unknown.
Convenience: Inserted before intercourse and left in place at least six hours after; can be left in place for 24 hours, with additional spermicide for repeated intercourse.
Availability: Prescription
Cervical Cap with Spermicide
Estimated Effectiveness: 60-80% (b)
Some Risks (c): Irritation and allergic reactions, abnormal Pap test
Protection from Sexually Transmitted Diseases (STDs): Spermicide may give some protection against chlamydia and gonorrhea; otherwise unknown.
Convenience: May be difficult to insert; can remain in place for 48 hours without reapplying spermicide for repeated intercourse.
Availability: Prescription
Sponge with Spermicide
Estimated Effectiveness: 60-80% (b)
Some Risks (d): Irritation and allergic reactions, difficulty in removal
Protection from Sexually Transmitted Diseases (STDs): Spermicide may give some protection against chlamydia and gonorrhea; otherwise unknown.
Convenience: Inserted before intercourse and protects for 24 hours without additional spermicide; must be left in place for at least six hours after intercourse; must be removed within 30 hours of insertion; used only once and discarded.
Availability: Nonprescription
Spermicides Alone
Estimated Effectiveness: 74%
Some Risks (c): Irritation and allergic reactions
Protection from Sexually Transmitted Diseases (STDs): May give some protection against chlamydia and gonorrhea; otherwise unknown.
Convenience: Instructions vary; usually applied no more than one hour before intercourse and left in place at least six to eight hours after.
Availability: Nonprescription
Oral Contraceptives--combined pill
Estimated Effectiveness: Over 95%
Some Risks (c): Dizziness; nausea; changes in menstruation, mood, and weight; rarely cardiovascular disease, including high blood pressure, blood clots, heart attack, and strokes
Protection from Sexually Transmitted Diseases (STDs): None, except some protection against pelvic inflammatory disease.
Convenience: Must be taken on daily schedule, regardless of frequency of intercourse.
Availability: Prescription
Oral Contraceptives--progestin-only minipill
Estimated Effectiveness: 95%
Some Risks (c): Irregular bleeding, weight gain, breast tenderness, slightly increased chance of ectopic pregnancy
Protection from Sexually Transmitted Diseases (STDs): None, except some protection against pelvic inflammatory disease.
Convenience: Must be taken on daily schedule, regardless of frequency of intercourse.
Availability: Prescription
Emergency Contraceptives
Estimated Effectiveness: 75% (d)
Some Risks (c): Nausea, vomiting, menstrual changes, breast tenderness
Protection from Sexually Transmitted Diseases (STDs): None
Convenience: Taken in two doses of medication.
Availability: Prescription
Injection (Depo-Provera)
Estimated Effectiveness: Over 99%
Some Risks (c): Irregular bleeding, weight gain, breast tenderness, headaches
Protection from Sexually Transmitted Diseases (STDs): None
Convenience: One injection every three months
Availability: Prescription
Implant (Norplant)
Estimated Effectiveness: Over 99%
Some Risks (c): Irregular bleeding, weight gain, breast tenderness, headaches, difficulty in removal
Protection from Sexually Transmitted Diseases (STDs): None
Convenience: Implanted by health-care provider--minor outpatient surgical procedure; effective for up to five years.
Availability: Prescription
IUD (Intrauterine Device)
Estimated Effectiveness: 98-99%
Some Risks (c): Cramps, bleeding, pelvic inflammatory disease, infertility, perforation of uterus
Protection from Sexually Transmitted Diseases (STDs): None
Convenience: After insertion by physician, can remain in place for up to one or 10 years, depending on type.
Availability: Prescription
Periodic Abstinence
Estimated Effectiveness: About 75% (varies, based on method)
Some Risks (c): None
Protection from Sexually Transmitted Diseases (STDs): None
Convenience: Requires frequent monitoring of body functions (for example, body temperature for one method).
Availability: Instructions from health-care provider
Surgical Sterilization--female or male
Estimated Effectiveness: Over 99%
Some Risks (c): Pain, bleeding, infection, other minor postsurgical complications
Protection from Sexually Transmitted Diseases (STDs): None
Convenience: One-time surgical procedure
Availability: Surgery
Footnotes
(a) Effectiveness rate for polyurethane condoms has not been established.
(b) Less effective for women who have had a baby because the birth process stretches the vagina and cervix, making it more difficult to achieve a proper fit.
(c) Serious medical risks from contraceptives are rare.
(d) Treatment initiated within 72 hours after unprotected intercourse reduces risk of pregnancy by at least 75 percent.
