Men are over-represented at the high end of math performance: there are more male math geniuses than female ones.
A theory that was proposed to explain that fact is that of stereotype threat. According to this theory, there is a stereotype in society that "women are bad in math"; women internalize this stereotype and lose confidence about their math abilities, and so they tend to perform sub-optimally in math tests, hence rendering the idea of "women are bad in math" a self-fulfilling prophecy.
This new study demonstrates that much of the literature that has accumulated around the idea of a "stereotype threat" can be relegated to the trash bin, and those who hope that fighting the stereotype will lead to more females joining the mathematical elite have their work cut out for them.
A video on the topic by the first author:
Review of General Psychology, Jan 16 , 2012, No Pagination Specified. doi: 10.1037/a0026617
Can stereotype threat explain the gender gap in mathematics performance and achievement?
Stoet, Gijsbert; Geary David C.
Men and women score similarly in most areas of mathematics, but a gap favoring men is consistently found at the high end of performance. One explanation for this gap, stereotype threat, was first proposed by Spencer, Steele, and Quinn (1999) and has received much attention. We discuss merits and shortcomings of this study and review replication attempts. Only 55% of the articles with experimental designs that could have replicated the original results did so. But half of these were confounded by statistical adjustment of preexisting mathematics exam scores. Of the unconfounded experiments, only 30% replicated the original. A meta-analysis of these effects confirmed that only the group of studies with adjusted mathematics scores displayed the stereotype threat effect. We conclude that although stereotype threat may affect some women, the existing state of knowledge does not support the current level of enthusiasm for this as a mechanism underlying the gender gap in mathematics. We argue there are many reasons to close this gap, and that too much weight on the stereotype explanation may hamper research and implementation of effective interventions.