Have you ever wondered why most engineers are men while most nurses are women?
A new study suggests that is has nothing to do with societal pressure and everything to do with hormones.
Psychologists at Penn State University have investigated why certain professions are predominantly one sex.
They found that sex hormones strongly influenced people's interests, which in turn affected the kinds of occupations they chose.
Women were more likely to choose careers that allowed them to work with people, like nursing and teaching, while people with higher levels of male sex hormones preferred to work with things, seeking careers in science, mathematics and engineering.
Study leader Sheri A. Berenbaum and her team studied teenagers and young adults with congenital adrenal hyperplasia (CAH) — a genetic condition that develops when foetuses are exposed to higher levels of the male sex hormone androgen in the uterus.
They compared the interests, skills and career aspirations of the people with CAH to those of their non-CAH siblings.
They found that while women with CAH were genetically female, their interests tended to be more stereotypically male. They were also significantly more interested in careers in maths, science and engineering than other females.
The report, published in the current issue of Hormones and Behavior, also found that career interests directly corresponded to the amount of androgen the CAH females had been exposed to, with those exposed to the highest levels showing the most interest in career that involved things instead of people.
There was no difference reported between males with CAH and males without the condition.
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