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Re: This could be due to increasing testosterone: the secular trend.

It is my hypothesis that the "secular trend," the increase in size and earlier puberty in children is caused by an increase in the percentage of individuals of higher testosterone within the population over time. The driving force is an increase in women of higher testosterone within the population over time. This exposes their fetuses to higher levels of testosterone in utero. In groups which began the trend with already high testosterone, I suggest this increase in testosterone is the cause of the current increases in diabetes, obesity, infections, low birth weight and preterm babies, breast cancer and other cancers, etc within the population over time. In groups in which the testosterone levels were not high in the past, I suggest the secular trend may produce positive, overall benefits. I suggest this may explain why professional schools are increasing admitting and graduating increased numbers of women.