study by the Population Reference Bureau report 500,000 girls the preliminary findings estimation report estimated Population Reference Bureau Claims that Female Genital Mutilation the highest prevalence From the February 2015 Population Reference Bureau report women and girls at risk reports From the February 2015 Population Reference Bureau report estimation Population Reference Bureau, FGM in America http://www.prb.org/Publications/Articles/2015/us-fgmc.aspx estimated new report women and girls at risk reports