IT IS the last thing Iran’s religious rulers want to talk about, but they may just have to. An official report has documented the nation’s worst-kept secret: sex of every kind is taking place outside the marital bed in the Islamic Republic. Something, in the ruling ayatollahs’ view, must be done.

An 82-page document recently issued by Iran’s parliamentary research department is stark in its findings. Not only are young adults sexually active, with 80% of unmarried females having boyfriends, but secondary-school pupils are, too. Illicit unions are not just between girls and boys; 17% of the 142,000 students who were surveyed said that they were homosexual.

In Tehran, the capital, long known for its underground sex scene, chastity is plainly becoming less common. The scope and pace of change are challenging the government and posing a headache for the clerics who dispense guidance at Friday prayers.

The report is also a rare official admission of the unspoken accord in Iran: people can do what they want so long as it takes place behind closed doors. Parliament’s researchers, on this occasion, were allowed to say the unsayable.

Their suggestion for stopping unsanctioned sex is remarkably liberal. Instead of seeking to cool the loins of the youngsters altogether, they should be allowed publicly to register their union by using sigheh, an ancient practice in Shia Islam that lets people marry temporarily. A legal but loose and much-deprecated arrangement, which can last from a few hours to decades, sigheh is often viewed as a cover for promiscuity or prostitution. Clerics themselves have long been suspected of being among its biggest beneficiaries, sometimes when they are on extended holy retreats in ancient religious cities such as Qom.

For less conservative Iranians, some of whom even jokingly describe themselves as “not real Muslims”, the report is merely an admission of reality—and an amusing distraction from the austere topics usually occupying their leaders’ minds. “This is what every human body needs,” says Zahra, a 32-year-old chemist who lives with her boyfriend in northern Tehran and declares that she has no intention of seeking authorisation to have sex. “I have one life and though I love my country, I cannot wait for its leaders to grow up,” she adds.

Iran’s media, always wary of being shut down, have played safe by ignoring the report. So have members of parliament. In most official circles, sex in Iran is still too hot to talk about.