CONTENTS
Chapters
- The Condom Gap: A Health Crisis
- Sexual Behavior and Condoms
- Knowledge of Condoms and AIDS
- How Effective Are Condoms?
- New Condoms for the New Millennium
- Improving Access
- Promoting Condoms
- Policies for Condom Use
HIGHLIGHTS
Population Reports is published by the Population Information Program, Center for Communication Programs, The
Johns Hopkins School of Public Health, 111 Market Place, Suite 310, Baltimore, Maryland
21202-4012, USA
Volume XXVII, Number 1
April, 1999
Series H, Number 9 |
How Effective Are Condoms?
Condoms can be effective at preventing both pregnancy and sexually transmitted infection
(STIs). For condoms to be effective, however, people must use them consistently and correctly.
Effectiveness Against Pregnancy
Studies of contraceptives often consider two different measures of effectiveness: perfect use
effectiveness and typical use effectiveness. Perfect use effectiveness is the effectiveness of a
contraceptive method when it is used correctly and with perfect consistency; it takes into account
only technical failures of a contraceptive method—for example, sperm leaking through a hole in
a defective condom. Because perfect use effectiveness can be difficult to gauge apart from actual
use, most reports equate perfect use effectiveness with the best rates of effectiveness observed in
actual use (537, 538, 575). In contrast, typical use effectiveness takes into account all reasons
that unintended pregnancies occur, including people's occasional failure to use the method,
incorrect use, and technical failures of the method.
Perfect use effectiveness. Among people who use condoms consistently and correctly, pregnancy
rates are fairly low—about 3 pregnancies per 100 women in the first year of use. By comparison,
sterilization, Norplant® implants, the TCu-380A IUD, long-acting injectables, and, when used
correctly, oral contraceptives have the lowest observed rates of about one pregnancy or less per
100 women in the first year of use (538).
Typical use effectiveness. Typical use effectiveness varies greatly in various studies and among
groups within studies. For example, DHS data suggest pregnancy rates per 100 first-year condom
users of over 16 in Egypt, almost 6 in Indonesia, and over 8 in Thailand (20). The estimated
typical pregnancy rate among condom users in the US is about 14 per 100 women. This rate is
higher than for most other methods (367, 537, 538). |
