I think a major issue with CS in particular is that the numbers have actually gone down significantly in the past few decades:
> Before 1970, women took between 10% and 15% of computer science bachelor’s degrees. By the early 1980s, the number rose to 37%. However, the trend began to reverse in 1985. In 2013, 18% of bachelor’s degrees in computing were earned by women. Part of this decline is due to the fact that computer science became a male-identified field. But during the 1990s, hiring practices also began to favor men, according to the AAUW study, and “the creation of professional organizations, networks, and hierarchies” that supported the entry of men into the field helped pushed women out. In fact, as the study notes, once employed in the field, women are more likely to leave than men. They tend to suffer from isolation.
> Before 1970, women took between 10% and 15% of computer science bachelor’s degrees. By the early 1980s, the number rose to 37%. However, the trend began to reverse in 1985. In 2013, 18% of bachelor’s degrees in computing were earned by women. Part of this decline is due to the fact that computer science became a male-identified field. But during the 1990s, hiring practices also began to favor men, according to the AAUW study, and “the creation of professional organizations, networks, and hierarchies” that supported the entry of men into the field helped pushed women out. In fact, as the study notes, once employed in the field, women are more likely to leave than men. They tend to suffer from isolation.
http://fortune.com/2015/03/26/report-the-number-of-women-ent...