In the tipsy-topsy world we live in, this is known as a "controversial" idea. Unlike, say, alternative visions of human sexuality -- such as that it is empowering for young women to have sexual adventures outside of marriage, so long as they use condoms.
Thanks to a really interesting database called the National Longitudinal Study of Adolescent Health, researchers have been able to track the effects of virginity pledges on teens' actual sexual behavior.
The first batch of research (by Peter Bearman and Hannah Bruckner) was released in 2001. Looking at a nationally representative sample of teens age 12 to 18, the researchers concluded that pledges work. Teens who take them delay sex on average an extra year and a half.
"The delay effect is substantial and almost impossible to erase," the researchers note. However, the pledge worked because it created an "identity movement," a "moral community" that is effective only if the group was not too small and also not too large. (If everyone pledges, then the pledge is no longer a distinctive badge of moral identity.)
Other interesting findings: Clear, explicit parental disapproval of sex also helped teens, including older teens, avoid sex: "Perceived parental disapproval of sex, however, is a strongly delaying factor throughout adolescents."
In general, the more connections and activities the teens had, the less likely they were to have sex. With one exception: "The more frequently and the earlier adolescents date, the earlier they have intercourse." If you don't want your teens having sex, tell them so. Tell them why. And delay the onset of the dating game.
In an update released last month (the teens are now 18 to 24 years old), the same researchers focused on the trouble with pledges. They are not a miracle cure. Most pledgers eventually have nonmarital sex. While their rates of sexually transmitted diseases were slightly lower, the difference between pledgers and nonpledgers was not statistically significant -- even though pledgers reported significantly fewer total sexual partners than nonpledgers. Apparently they use condoms and seek medical care for STDs less often.
The amazing thing is that, six years later, the pledge taken years ago in high school appears to still have an effect: Pledgers were still less likely than nonpledgers to have initiated sex, and they were more likely to marry, too. Although remaining a virgin until marriage was rare, pledgers were 12 times more likely to be virgins when they married.
As a result, according to a recent Heritage Foundation analysis
For example, 21 percent of white girls who had not taken a pledge had already become unwed mothers (by ages 18 to 24) compared to 13 percent of pledgers. More than a third of black girls who did not pledge were unwed moms, compared to less than a quarter of black girls who took the pledge. Given the high costs of unmarried childbearing to women, to children and to society, the effect of pledging and other abstinence interventions on out-of-wedlock childbearing deserves more attention from researchers.
But instead, the original pledge researchers concluded on a remarkably negative note: "Just saying 'no' or just encouraging adolescents to say 'no,' while appearing to be effective in the short-term, does not reduce the risk of STD acquisition in the long-term. We need to recognize that there are effective interventions and that these interventions are based on real social science research and not ideology."
One of the most consistent social science research findings is that one thing that works for teens is adults -- teachers, preachers and, even more important, parents -- who dare to send the powerful and consistent messages that empower teenage girls to make better sexual decisions, such as: True Love Waits.