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).

Fabian tactics

Little is known about the influence of sexual timing on how relationships develop. Even so, opinions abound. Some argue that the sexual organs, both physical and mental (for, as the old saw has it, the most powerful erotic organ is the mind) need a test drive to make sure the chemistry between a couple means they will stay together both in sickness and in health. Others suggest that couples who delay or abstain from sexual intimacy early on allow communication to become the foundation of their attraction, and that this helps to ensure that companionship and partnership keep them together when the initial flames of lust die down.

To examine these suggestions more closely, Dr Busby and his colleagues recruited 2,035 married people ranging in age from 19 to 71, and in length of marriage from less than six months to more than 20 years. Their religious affiliations varied widely; many had none.

All were asked to complete an online questionnaire normally used to help couples understand their strengths and weaknesses. Among the nearly 300 questions, participants were asked when they first had sex with their partners, whether their sex lives were currently good, how they resolved conflicts, and how often they thought of ending their relationship. In addition, the questionnaire had 14 items that evaluated how good participants were at expressing empathy and understanding to their partners and how prone they were to be critical or defensive. All questions, apart from those about frequency of sex, were answered on a five-point scale, with one indicating strong disagreement and five indicating strong agreement.

Because religiosity delays sexual activity, Dr Busby and his colleagues also asked participants how often they attended church, how often they prayed and whether they felt spirituality was an important part of their lives. They used the answers to control for religiosity. They also controlled for income, education, race and length of relationship.

Their report, just published in the Journal of Family Psychology, suggests that people who delay having sex do indeed have better relationships, on four different measures (see table). That result applies to both men and women.

Unfortunately, Dr Busby's method cannot distinguish the cause of this. It could be, as many moralists preach, that the delay itself is improving. It could, though, be that the sort of people who are happy to delay having sex are also better at relationships. Correlation, in other words, rather than causation. That is material for another study. If the result persists, though, even when personality is taken into account, it will provide useful ammunition for priests and marriage-guidance counsellors.