From NPR in August, Many Women Leave Engineering, Blame the Work Culture.

• Close to 40 percent of women with engineering degrees either leave the profession or never enter the field
• The biggest pushbacks female engineers receive come from the environments they work in
• Compared with other skilled professions such as accounting, medicine and law, engineering has the highest turnover of women
• “We’ve found that women stay in engineering because they want to make sure they are making a difference,” she says. “If women feel they are making that difference, retention levels will be higher.”