I don't know the order of importance, but these are the causes: * endocrine disruptors from while the baby is in the womb through before puberty, primarily BPA, Atrazine, Perfluoroalkyl substances, Organophosphates, Phthalates, Carbamates, Pyrethroids, and Glyphosate. These chemicals cause the part of the brain responsible for sex drive to wire incorrectly towards the wrong sex. I think hormonal birth control is also a factor. * sexual molestation. I think a lot of the increase is growing up in a chemical soup consisting of goyslop, mothers being on hormonal birth control, toxic plastics, and poisonous chemicals used in modern agriculture.