The Health and Human Services Department declined an interview request to discuss the announcement.

Groups that have been receiving federal money had been bracing for a change in the rules since last year, when Valerie Huber, a leader of an abstinence education advocacy organization, was named chief of staff to the Department of Health and Human Services official who oversees adolescent health. Shortly before she was appointed, Ms. Huber wrote in an opinion piece that the best message for young people was “to avoid the risks of teen sex, not merely reduce them.” She described the Obama administration’s approach as one that “normalizes teen sex.”

The new rules also move away from a requirement that most organizations receiving federal money choose from a list of approaches that have been shown in at least one rigorous evaluation to be effective at changing some sexual behavior, such as reducing pregnancy rates or rates of sexual activity.

Under Obama administration guidelines, organizations awarded most of the grants had to use curriculums that were on an evidence-supported list. Under the new guidelines, they simply have to comply with more general requirements like “support personal attitudes and beliefs that value sexual risk avoidance.”

Jon Baron, vice president of evidence-based policy at the Laura and John Arnold Foundation, a nonpartisan foundation, said the new approach is like “starting from ground zero as if nothing has been learned. Until you have an evaluation of an actual program that people are showing up for and an actual curriculum and actual people teaching it, you really don’t have reliable evidence.”

Abstinence programs have often failed to change teenage sexual behavior. A 2007 study of four such federally funded programs, for example, found “not even a hint of an effect on sexual activity, pregnancy or anything,” Mr. Baron said. Still, the Obama administration’s menu of “evidence-based programs” included three abstinence programs.