Source: 123RF.com/Sergejus Bertasius

In the United States today, 37 states mandate that information on abstinence be provided in sex education courses. It is not uncommon for students in those states to be asked to take “purity” or virginity pledges as part of their curriculum.

Students are encouraged to take these pledges in order to both reduce the spread of sexually transmitted infections and to prevent unintended pregnancies. As it turns out, however, abstinence pledges don’t necessarily accomplish either one of these things. In fact, a recent study published in the Journal of suggests that they may do precisely the opposite!

In this study, researchers utilized data from a nationally representative, longitudinal survey of adolescents (Add Health). Data were collected at several intervals between 1994 and 2008, and all participants were adolescents in grades 7-12 at the time the study began.

For this particular publication, researchers focused on two subgroups. First, they looked at how taking a virginity pledge was associated with likelihood of being diagnosed with HPV specifically among sexually active women who provided urine samples in 2001-2002 that were tested for this virus. There were 3,254 women in this analysis, of whom 15% reported having taken a previous virginity pledge.

Second, they looked how taking a virginity pledge was associated with becoming outside of among girls who were in grades 7 and 8 when the study began and who had not yet had intercourse at that time. There were 1,335 women in this analysis, of whom 23% reported having taken a previous virginity pledge.

So what did they find? Among women with two or more partners, those who had taken virginity pledges were more likely to have tested positive for HPV than those who hadn’t taken such pledges. The biggest difference was among women with 6-10 partners—in this group, 51% of pledge takers had contracted HPV compared to 33% of those who had not taken a pledge.

In addition, pledge takers were significantly more likely than non-takers to become pregnant outside of marriage within six years of their first sexual intercourse—30% vs. 18%, respectively. In both groups, the vast majority of these pregnancies were unplanned (75-80%).

So how do we explain this pattern of results? The authors of the research argued that “both sets of results are consistent with the notion that pledge breakers were less likely to be consistent users of condoms; as their exposure risk increased, they had increased risk of negative health outcomes.”

It seemed that those who took virginity pledges were less prepared when it came to practicing safe sex, perhaps because abstinence-only sex courses have a tendency to downplay the effectiveness of condoms and contraceptives. However, it could also be that perhaps these folks were simply less prepared to communicate about sex in general with their partners.

Whether the same could be said of men who do and don't take virginity pledges remains unclear because they were not considered in this study. Also, it’s important to note that virginity pledges probably don't increase the risk of STIs and unintended pregnancies for everyone. Some folks, particularly those with a high degree of religious commitment, may be less inclined to break pledges of this nature and, therefore, may actually have better sexual health outcomes.

That said, it appears that abstinence pledges often have unintended consequences. Indeed, when these pledges are broken, women's risk of negative outcomes is higher than it would be if they had never taken such a pledge in the first place.

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