Taking an abstinence pledge made teenagers no less likely to have sex before marriage but significantly less likely to use contraceptives when they did have sex, the Washington Post reports. “Previous studies would compare a mixture of apples and oranges,” said Janet Rosenbaum, the author of a new study that sought to weed out the demographic differences in other, similar studies. “I tried to pull out the apples.”
“Somebody who decides to take a virginity pledge tends to be different from the average American teenager,” Rosenbaum said. So she identified non-pledgers who were similar to the pledgers based on 100 variables, including their attitudes toward sex. The result? Both groups had sex before marriage at the same rate, but pledgers were 10% less likely to use protection.