The U.S. government spends more than $200 million annually on abstinence-promotion programs, including virginity pledges.
The latter approach does not work too well.
A new study of a federal survey taken in the 1990s finds that teens who took virginity pledges are just as likely as other teens to have sex before marriage. Importantly, when the pledgers broke their vows they were less likely to use birth control, including condoms.
"Taking a pledge doesn't seem to make any difference at all in any sexual behavior," said Janet E. Rosenbaum of the Johns Hopkins Bloomberg School of Public Health, whose led the study. "But it does seem to make a difference in condom use and other forms of birth control that is quite striking."
These teens who'd promised to avoid premarital sex actually ended up exposing themselves to greater risk of pre-marital pregnancy and sexually transmitted disease, despite the hopes of those who support federally funded virginity pledge programs.
The findings, reached by comparing teens with similar values (some of whom took the pledge and some who did not) are not news to researchers who have examined teen surveys about pledges in the past. A 2005 study reached similar conclusions, also showing that most of those who pledged deny ever having made the promise. The new research confirms this, too.
"Five years after the pledge, 82 percent of pledgers denied having ever pledged," the researchers write in the January issue of the journal Pediatrics.
"Pledgers are less likely to protect themselves from pregnancy and disease before marriage," the scientists write. "Virginity pledges may not affect sexual behavior but may decrease the likelihood of taking precautions during sex. Clinicians should provide birth control information to all adolescents, especially virginity pledgers."
Advocates of abstinence complain that Rosenbaum and her colleagues are using the study to make ideological arguments in the long-running political/religious/health debate over sex education and the promotion of contraceptives vs. abstinence among young people.
"It is remarkable that an author who employs rigorous research methodology would then compromise those standards by making wild, ideologically tainted and inaccurate analysis regarding the content of abstinence education programs," said Valerie Huber of the National Abstinence Education Association.
The study, and others before it, also raises questions about what parents can do to protect their children from unwanted pregnancy and disease, and whether they really know what their teens are up to.
In a 2006 study, Rosenbaum found that adolescents who'd had premarital sex and then decided to make a virginity pledge were likely to misreport their earlier sexual history. This misreporting of sexual experience makes it difficult to accurately assess virginity pledges' effects on early sexual intercourse, she said at the time.
Yet another take on the new study, by Dr. Bernadine Healy writing for U.S. News & World Report, seems to dig into the study's data a little deeper than many media.
Healy agrees that the act of making a virginity pledge doesn't appear to affect a teen's future sexual behavior. "But the kind of teen who takes a pledge is the kind who's already likely to be sexually restrained throughout adolescence," she writes. "There's an important message here for parents: The focus should be on cultivating the teenager's ongoing home and social environment, rather than on eliciting a one-time, easily-forgotten promise."
Robert Roy Britt is the Editorial Director of Imaginova. In this column, The Water Cooler, he takes a daily look at what people are talking about in the world of science and beyond.
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Robert is an independent health and science journalist and writer based in Phoenix, Arizona. He is a former editor-in-chief of Live Science with over 20 years of experience as a reporter and editor. He has worked on websites such as Space.com and Tom's Guide, and is a contributor on Medium, covering how we age and how to optimize the mind and body through time. He has a journalism degree from Humboldt State University in California.