OF ALL the ways in which women and girls are made to suffer because of their sex, infibulation is perhaps the worst. Each year 400,000 are subjected to this atrocity in which the external genitals are excised and the vagina stitched almost completely closed (see article). More than 4m undergo some form of female genital mutilation (FGM) each year—a range of practices, from infibulation at one end, through incisions or pricks that hurt but cause no lasting damage, to the merely symbolic, such as rubbing the genitals with herbs.

For three decades campaigners, led by the UN, have tried to end all FGM. They have pushed for bans and prosecutions; trained medical practitioners to refuse requests for it; lobbied religious leaders to oppose it (though FGM is not mentioned in the Koran, many Muslims regard it as part of their faith); and tried to persuade parents of its dangers. They have had some success. Between 1985 and 2015 the countries where FGM is most common saw the share of girls cut fall from 51% to 37%.

There are good arguments for a blanket ban on FGM. One is that medical procedures with no possible benefit are unethical—especially when inflicted without consent, on children. Another is revulsion at FGM’s misogynist roots: the motive is generally to cleanse the girl of some supposed impurity and tame her sexual desires, thus ensuring her virginity until marriage and fidelity thereafter.

But progress has been slow, especially in the African countries where the worst forms are common. On current trends, most girls in Somalia and Djibouti will see their own daughters mutilated, too.

It is therefore time to consider a new approach. Instead of trying to stamp FGM out entirely, governments should ban the worst forms, permit those that cause no long-lasting harm and try to persuade parents to choose the least nasty version, or none at all. However distasteful, it is better to have a symbolic nick from a trained health worker than to be butchered in a back room by a village elder. If health workers also advised parents that even minor rituals are unnecessary, progress towards eradication could continue.

Might “harm reduction” lend spurious legitimacy to all types of FGM? Yes, but it has worked in other fields. Shooting galleries for heroin reduced HIV without increasing drug-taking. Free housing keeps homeless alcoholics out of hospital and, by making their lives less chaotic, helps them drink less.

A different comparison, with male circumcision, is also instructive. Unless botched, that procedure causes no lasting pain or impairment—but it also has no medical justification (except to slow the spread of HIV in countries where it is common). Nonetheless, circumcision is widely accepted, because of its cultural and religious significance. Activists focus on unhygienic traditional versions.

From worse to merely bad

No one knows whether parents could be persuaded to abandon the worst horrors of FGM for versions that, while still pointless and painful, would not leave their daughters damaged for life. That is because no one has tried. Various Western doctors have advocated offering minor forms of genital cutting to sub-Saharan immigrants, in the hope of sparing their daughters from a trip home for infibulation. Each time the outrage—from the UN, activists and many other medics—has forced them to retract.

Faced with the urgency of saving 400,000 girls from severe mutilation each year, arguments without evidence are not good enough. There is only one way to find out whether FGM can be ameliorated more quickly than ended: try it and see.