A new study shows for the first time that a sex education class emphasizing abstinence only -- ignoring moral implications of sexual activity -- can reduce sexual activity by nearly a third in 12- and 13-year-olds compared with students who received no sex education.
Other forms of sex education also worked, however, reducing sexual activity by about 20% and reducing multiple sexual partners by about 40%, according to the study reported Monday in the Archives of Pediatrics and Adolescent Medicine.
None of the classes appeared to influence the use of condoms or other birth control when the students did have sex. The children thus remained at risk of pregnancy and disease.
"This study, in our view, is game-changing science," said Bill Albert, chief program officer at the National Campaign to Prevent Teen and Unplanned Pregnancy, a nonprofit, nonpartisan group based in Washington. "It provides, for the first time, evidence that abstinence-only intervention helped young teens delay sexual activity."
The George W. Bush administration poured tens of millions of dollars into federal funding for abstinence-only programs, most of them religious-oriented, with little or no evidence that they worked. And new data released last week showed that sexual activity, pregnancies and sexually transmitted diseases are increasing among teens.
The Obama administration has sharply reduced funding for abstinence-only programs and has announced its intention to fund only interventions that have been found to work. The new study is expected to provide support for such interventions.
But Albert noted that this is only one study in one region. It "should not be interpreted as a signal that abstinence-only education works at all times and under all circumstances. That doesn't even pass the common-sense test."
In an editorial accompanying the report, journal editor Dr. Frederick P. Rivara of the University of Washington and Dr. Alain Joffe of Johns Hopkins University argued that "no public policy should be based on the results of one study, nor should policymakers selectively use scientific literature to formulate a policy that meets preconceived ideologies."
The study's lead author, psychologist John B. Jemmott III of the University of Pennsylvania School of Medicine, agreed in a statement, saying that other types of students must be studied as well: "Policy should not be based on just one study, but an accumulation of empirical findings from several well-designed, well-executed studies."
The study was conducted among 662 African American sixth- and seventh-graders in four low-income schools in the northeastern United States. The students were randomized into four groups.
One received an eight-hour abstinence-only class focusing on the risks of pregnancy and sexually transmitted diseases. It was based on principles shown to be effective in reducing transmission of sexually transmitted diseases and did not use a moralistic tone or portray sex in a negative light.
A second group received an eight-hour safe-sex class. The third group received a comprehensive eight- or 12-hour class emphasizing both aspects. The control group received education only about healthy living.
Over the two years after taking the classes, 48.5% of those in the control group reported sexual activity, compared with 33.5% of those in the abstinence-only group. About 52% of those taught only safe sex reported sexual activity, and about 42% of those in the comprehensive class made a similar report.
About 8.8% of participants in the comprehensive class reported activity with multiple partners, compared with 14.1% in the control group, indicating that the comprehensive class reduced the risk of sexually transmitted disease. Diseases and pregnancies were not monitored, however.
Catherine Camacho, deputy director for the California Department of Public Health's Center for Family Health, said previous research had shown that it made sense to include abstinence education as part of a comprehensive program.
"A comprehensive approach that does include abstinence is the most effective program," she said. "We have never disagreed with that. But we would prefer to call it abstinence-plus."