Although women are earning more degrees in science, engineering, and technology than in previous decades--over 50% of U.S. undergraduate degrees in the life sciences now go to women--they continue to be drastically underrepresented at further career stages, and particularly in top positions. Women make up 10% of the membership of the National Academies of Science. Women's participation is higher in some areas than others: there are 82 members of the engineering sciences section, and 2 of them are women.
The international council of national academies of science has released a report on the status of women in the sciences. The report emphasizes solving the leakiest parts of the pipeline--graduate education, workplace advancement, and centers of prestige such as national academies themselves. It argues that women's ability to advance into the top tier of research scientists has as much to do with management and social environment as it does with individual women's promise and achievements.
A tragic expression of the frustration that women encounter is covered in this news story about the death of Denice Denton, chancellor of UC Santa Cruz.
On a side note, the representation of women in philosophy is higher than in engineering, roughly equivalent to physics, and lower than other sciences.