Chastity before marriage may have its uses after all

WHEN is it the right time to do the deed? If priests had their way, it would be shortly after the wedding ceremony—but recent studies show such advice is rarely heeded. Roughly 85% of the American population, for example, approves of premarital sex. Faced with numbers like that, what hope do the Vatican and its ilk really have?

More than they did a week ago. Until now, the argument that couples should wait until they are married before they have sex has rested on mere assertion and anecdote. Dean Busby and his colleagues at Brigham Young University, in Utah, however, have gathered some data which support delay (conveniently for the university, which is owned by the famously abstinent Mormons). …