FEMALE genital mutilation (FGM) is a surgical procedure—conducted for reasons of ritual and tradition—that ranges in severity from nicking the clitoris, to cutting off the clitoris and labia entirely and sewing up the vaginal opening. The practice, which is often performed by people with no medical training, is dangerous and causes serious health problems in later life, especially during childbirth. UNICEF estimates that 125m girls and women alive today have been subjected to some kind of FGM in the Middle Eastern and African countries where it is most common.

So it is good news that in one of them, FGM is set to be banned. On November 23rd the president of Gambia announced that the practice, which affects three-quarters of women and girls in the country, would be outlawed immediately. Yet changing the law may count for little without changing tradition. More than 60% of women said they thought the practice should continue, a disparity also seen elsewhere. The practice has declined in many countries, but most dramatically where it was already rare. The rate of decline is not enough to counter population growth, however. Unless the pace picks up, the number of victims will grow from 3.6m a year now to 4.1m in 2035. As the United Nations launches a campaign to end violence against women this week, Gambia's actions are a signal that culturally sanctioned violence will, at least, no longer be legally condoned.