I do not know about this, but I am tempted to revise my earlier proposal and include free will versus coersion.
I am wondering if a woman who wilingly, without any form of coercion social of otherwise (though I doubt such a woman exist) decides to get cut, would that still be refered as FGM? If so, this would help us make the distinction between the male circumcision which, by the way has been supported by WHO on hygienic grounds; see
http://news.bbc.co.uk/2/hi/health/6502855.stm and FGM