Would you like to become a mathematician, or rather stick to being a woman? There are of course many people who are both, and very successful ones at that, but the fact remains that women are still under-represented in maths-based careers and degree courses. They are also twice as likely to drop out of maths-based careers as men. Now a new study suggests that this may be due to the strain a maths environment puts on women's self-perception; a strain that works through unconscious gender stereotypes.

In an article published in the January issue of Psychological Science, psychologists Amy Kiefer of the University of California, San Francisco, and Denise Sekaquaptewa of the University of Michigan report on a study they carried out on undergraduates that were enrolled in an introductory calculus class. They rated women's implicit gender stereotypes, for example by checking if they automatically associated "male" with maths ability, and their self-perception, for example by asking if they identified themselves as feminine. They then followed their performance independently of the maths ability they had displayed previously.

The researchers found that the worst performers were those that had strong implicit gender stereotypes and were likely to identify themselves as feminine. This may seem unsurprising, but the important point is that the women's stereotypes were unconscious: the majority of women taking part in the study had explicitly stated that they do not believe that men are better at maths than women.

Another interesting point is the extent to which under-performance seems to be linked to gender identification. The authors suggest that this may give some insight into the high drop-out rate of women in maths-based careers. Women may feel that to be in tune with their work environment, they need to distance themselves from feminine characteristics. And the more they value these characteristics, the bigger the sacrifice that this involves, so that even women who are very good at what they do may come to leave their field.

It's sad to see how deep-seated women's stereotypes about their own abilities are, but there is hope. In recent decades women's participation in maths and science has increased drastically. There are many highly successful women mathematicians that can serve as role models. And once a critical mass has been reached, even the most ingrained stereotype can be overturned by experience.