I remember a few days before the start of my freshman year of high school, I was at the college library making copies of math competition tests so I could start practicing for the upcoming season of competition. While I was there, I saw a girl who was on the math team the year before in junior high, so I told her what I was doing and asked her if she wanted some practice tests. She said, "No," and just walked away, but there was a world in that "No." She was offended. She was insulted. She had been pretty good at the math competitions in junior high, but she quickly fell behind in high school and then quit the math team/club. She did drama and speech instead. She still took honors math classes and aced them, and I even heard she did engineering in college, but she would never admit to actually liking it enough to go beyond what was required by classwork.

Similarly, the girls I met in college who were getting degrees in math and engineering never admitted to having an interest in those subjects beyond doing well in their classes and getting degrees. The two girls in the math program were keen to express their interest in the money they would make as actuaries or what-not. They had to like math, or they never would have chosen to be math majors, but they never showed any sign of it, and (stung by my previous experience) I was scared to even imply that they might.

So yeah, there is a huge fear of nerdiness among women, and I don't think the "nerd chic" thing helps at all. There's no celebration in "nerd chic" culture of honestly frumpy people (there can't be in any "___ chic" culture, "___ chic" will never help anyone who isn't chic) so of all the girls I've known who I suspected of secretly liking math, maybe one of them would have felt at home there.

I went to high school in a small city (large town, really) in a rural area, and I went to college at a non-elite public school (went there for the honors program) so you guys who went the elite route may have seen vastly different things. In terms of numbers, though, I suspect my experience was more representative.