There is a good report done by the Swedish government body for higher education (which include the program that teach teachers), and it has multiple reasons stated. Two I strongly remember is that the education work culture has incorporate female gender identity (similar to "bro culture" in IT), and that the rate that male students leave the teacher program is significant higher than for female students. The few men that ends up finishing the program also tend to the leave the profession in higher rate than women.

The similarities are very striking to me to those made about IT profession, but with the roles reversed.