Sixth and seventh graders who took part in an abstinence-only education program were more likely to delay sex, according to a new study that could reignite the debate over what's the best method to reverse the teen pregnancy rate and prevent sexually transmitted diseases.

The study, appearing in today's Archives of Pediatrics & Adolescent Medicine suggests that abstinence-only programs that don't preach about morals may be effective in preventing young teens from engaging in sex, according to the authors of the NIH-funded study.

The research is billed as the first of its kind to measure the effectiveness of abstinence-only programs and comes on the heels of last week's news about a rise in the teen pregnancy rate , which set off yet another round of the contentious contraception vs. abstinence-only debate.

Researchers from the University of Pennsylvania enrolled 622 African-American students in either an 8-hour abstinence-only class, or one of three other classes that focused on condom use, other interventions and general health issues. Black teens are at especially high risk for unintended pregnancies, sexually transmitted diseases and HIV/AIDS.

By the three-year follow up mark, about a third of kids in the abstinence only course had had sex, while nearly half of the kids in the other courses had.

Critics of abstinence-only programs say they actually lead to less condom use if teens do end up having sex. But this study found that wasn't the case.

The findings don't settle the contraception vs. abstinence only debate, the authors are clear to note. Nor should this study signify that all abstinence only programs work.

"Tackling the problem of STIs among young people requires an array of approaches implemented in a variety of venues," they conclude. "What the present results suggest is that theory-based abstinence-only interventions can be part of this mix. Using theory-based abstinence-only interventions selectively might contribute to the overall goal of curbing the spread of STIs in both the United States and other countries."

Perhaps in anticipation of a heated policy debate, an accompanying editorial written by Dr. Frederick Rivara of the University of Washington and Dr. Alain Joffe of Johns Hopkins, offer a warning to those looking to use the findings to drive home a particular agenda. (We're not holding our breath.) The results of the study should be combined with other research to probe what kind of interventions work best, they said.

"No public policy should be based on the results of one study, nor should policy makers selectively use scientific literature to formulate a policy that meets preconceived ideologies," they write.