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| quote: | Originally posted by SYSTEM-J
Although I've heard the claim that puberty begins earlier in modern kids, which needs validating and then understanding if we're to start meaningful sex ed when puberty begins. |
Age at first menstruation has decreased by a little less than half a year since 1970:
| quote: | Reported mean age (± SD) at menarche showed a monotonic trend of decreasing over time, from 13.41 (± 1.30) years for women born before 1970 to 13.03 (± 1.28) years for those born after 1978 (P < .001). Women born after 1978 were twice as likely to experience menarche by the age of 11 as those born prior to 1970 (odds ratio 2.0; 95% confidence interval, 1.41–2.82).
http://www.ncbi.nlm.nih.gov/pmc/articles/PMC1327706/ |
May not sound like much, but as noted this means that you have a much larger number of girls becoming fertile right after elementary school. Crazy! Start of menstruation also has a relation with obesity; fatties become fertile earlier on. And everyone knows there are more fatties now, so...
There are some claims that it has decreased by at least a few years since 1900, but these are based on less reliable studies, as far as I know.
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