According to Elain McArdle at the Boston Globe, the reason why women aren't going these disciplines is: They just aren't interested.
And not only adult women are choosing fields other than science, most U.S. children, female and male aren't interested in putting in the heavy lifting necessary to learn about science and to get a useful degree.
An interesting hour speech by Joy Hakim on C-Span's Book TV gives hope that perhaps the situation my be altered due to a change in strategy put into motion by leading U.S. scientists that are hoping to "reinvigorate the teaching of science." (We are 21st in science and 25th in math).
In her speech she made a point that many classroom teachers already know: most reading material for young children is lacking in content, i.e. facts, concepts, etc.; And they are even boring! They also know young children are far more able to understand concepts that generally was acknowledged.
The Story of Science is a new and different series written by Hakim, backed by the Smithsonian in association with the National Science Teachers Association.
The books are done in narrative form, different from those aimed at producing top scientists. Let's face it: Few children will grow up to become "top scientists," but wouldn't it be wonderful is more of them would show and interest. Here is the "for Teachers link.
Although Hakim's writing about history is not without controversy, I have not found the same criticism of the science series.
Perhaps it's too new, but we need to do something to improve textbooks and the curricula.
The Story of Science: Aristotle Leads the Way; The Story of Science: Newton at the Center; The Story of Science: Einstein Adds a New Dimension and Teaching Materials at the National Science Teachers Association (NSTA).