"There are mostly, if not exclusively, psychological factors at play here, based on poor sexual skills that lead to a poor sexual debut, with lasting negative effects," said Patti Britton, president of the American Association of Sexuality Educators, Counselors and Therapists and Los Angeles-based author of books including "The Art of Sex Coaching."
Coleman, however, said that biological factors may also be involved.
"There are probably both biological and psychological factors at play -- which cannot be elucidated from this study -- but suggests that further research needs to be conducted to explore those factors," he said.
The researchers say this preliminary evidence may point up detrimental effects of abstinence-only education.
The authors write that the study "lends credence to research showing that abstinence-only education may actually increase health risks," adding that other approaches may better equip young people to avoid both short- and long-term sexual health consequences.
Many sexuality experts agree.
"In my view as a sexuality therapist since the 1970s, the abstinence-only approach is a public health hazard," Ogden said. "Sexual relationship is complex, and the moment of marriage is not a magic marker.
"Instead of making young people pledge 'no' until marriage, we need to be encouraging them to understand their own sexual responses and orientations, learn how to engage in sexual practices that are safe, and acquire intimacy skills that will lead them into caring relationships."
Said Coleman, "While abstinence only programs seem to be helpful in delaying onset of sexual activity, there have been suggestions that this approach could cause more problems when sexual debut takes place due to insufficient preparation and knowledge of responsible sexual behavior.
"This study is interesting because it suggests that sexual experimentation is a normal developmental process, and when this process is inhibited or not guided, there can be poor sexual health outcomes."