Simon Fraser University Psychology professor Doreen Kimura answers the first part:

I found a paper which might answer the question, focussing on humans: Berenbaum S.A. (1998) How hormones affect behavioral and neural development: Introduction to the special issue on "Gonadal hormones and sex differences in behavior". Developmental Neuropsychology, 14, 175-196. You can look this up in your local library.

Simon Fraser University mathematics professor Malgorzata Dubiel answered the second part for us:

First, connections between gender and math anxiety are much stronger in North America than many other countries, which suggests that this is closely related to cultural issues as well.

But, at least in North America, many more women suffer from math anxiety than men. Possible reasons:

1. Women are more likely to admit to suffering from math anxiety and seek help than men. In my work with math anxious students I met several cases of math anxious men, some of them extremely severe. But majority of students who come to me for help are women.

2. There is a widespread perception - though slowly diminishing - that men are better at math than women, and that women are less likely to need math in their lives and careers. These perceptions are still a reason that women are less likely to get help with math in school or encouragement to study math related subjects.

3. Many people believe that boys dominate classroom discussions and therefore girls perform better in math and sciences in an all-girls classroom.

4. Patterns in self-confidence: boys tend to blame their problems on not enough effort, girls - on lack of abilities.

5. Not enough female role models.

6. Perception that math is a "nerdy" subject and definitely not a "feminine" one.

These are some of the gender issues associated with math anxiety. To learn more, I highly recomment the book "Overcoming Math Anxiety" by Sheila Tobias.