One of the last acts of Nigeria's president Goodluck Jonathan was to sign a law — the Violence against persons (prohibition) act — which, from May 2015, bans female genital mutilation (FGM) across the country. Of the 140 million women and girls worldwide who have undergone procedures of this kind, a quarter live in Nigeria, according to the World Health Organization (WHO). Although the law is an important milestone, top-down directives alone are not enough to change cultural behaviours that have been passed down through generations.

What FGM is. FGM refers to traditional practices involving the mutilation of female genitalia for non-therapeutic reasons. The WHO classifies them into four types. The first is the removal of the tip of the clitoris. The third, infibulation — the most extreme — involves the stitching of the vulva. Girls often undergo these procedures before the age of fifteen, at the hands of traditional circumcisers or, increasingly, medical personnel.

FGM is most prevalent in western, eastern and north-eastern Africa, in certain countries in Asia and the Middle East, and in countries with migrant communities originating from these areas. Egypt is the country with the highest rate of FGM: more than 90 per cent of married women between the ages of 15 and 49 have undergone these types of procedures.

Why they are practised. FGM has origins that are ancient — predating Christianity and Islam — and unknown. The practices are sometimes justified on religious grounds, but no faith officially recognises them. Women of different faiths and social classes undergo genital modification, and the reasons vary depending on the place. Some of the most common reasons are to suppress female sexuality and to mark the transition from childhood to adulthood. Generally, the ultimate aim is to prepare girls for marriage.

The stigma affecting girls who have not undergone FGM is the main obstacle to eliminating these cruel traditions. It is the mothers themselves who decide to have these procedures carried out on their daughters, precisely to ensure they have good marriage prospects, as expert Gerry Mackie explains.

Why and how FGM is opposed. The health risks are many. FGM can cause complications such as infections and problems during childbirth. It is also considered a violation of human rights because it is a form of violence and oppression against women. In 2012, the United Nations General Assembly adopted a resolution calling for the abolition of FGM, which is also one of the targets of the UN's Sustainable Development Goals (SDGs) — 17 social and environmental priorities that will mobilise the international community over the next fifteen years.

FGM is illegal in 24 African states and in many Western countries. While bans are the main strategy for eradicating these traditions, they are not enough. In some countries, such as Egypt, the rate of prevalence has remained constant despite FGM being illegal. In Nigeria, for example, FGM has been banned in certain states for years, yet it continues to be widely practised.

The most effective strategies employ concrete measures that involve communities directly. Tostan is an African NGO: rather than trying to force communities to abandon these traditions, its Community empowerment programs (Cep) use human rights sessions to encourage dialogue on the subject. The result:

"More than 7,200 communities in Djibouti, Guinea, Guinea-Bissau, Mali, Mauritania, Senegal, Somalia and the Gambia have publicly declared their decision to abandon FGM." (Tostan)

From African villages to the conference rooms of UN summits, many voices are calling for FGM to be eradicated through approaches that work with, rather than against, the communities that practise it. As the case of Nigeria illustrates, where the prevalence of FGM has remained at around 30 per cent of women between the ages of 15 and 49 despite prohibitions. Laws help, but it is minds that need to change.