The survey of 1,517 teenagers in 2001 showed that 23.8 percent made pledges to remain chaste until marriage. Those who made the vow but broke it by 2004 comprise 34 percent of the respondents, while those who did not make a commitment to virginity and engaged in sex was 42 percent of the respondents.
The study takes a special significance as Republican Vice Presidential candidate Sarah Palin speaks at the GOP convention Wednesday, fresh from public disclosure that her 17-year old daughter, Bristol, is pregnant by her 18-year old boyfriend, highlighting the widespread practice of pre-marital sex by American adolescents.
Rand psychologist Steven Martino, the study's lead author, said it was a good idea for teenagers to make a pledge to refrain from indulging in sex because those who make the vow have higher chances of keeping their word.
Martino added, "But that's not to say virginity pledges should substitute for comprehensive sex education, because a majority of teens do have sex, and even among teens who take virginity pledges many of them have sex."
The Rand study was published online in the Journal of Adolescent Health. Its printed edition will come out this month.
