Mean Age Of Menarche In 1900 - 14.2 Years. Mean Age Today - 12.8 Years

[hatrack]

A 5-year-old girl with pubic hair. A pregnant 10-year-old. An increase of early labor. Nine-year-olds starting their periods. These are some of the more extreme examples of early puberty that Linda Williams has witnessed as CEO of Planned Parenthood Mar Monte. She’s not alone. There are scores of data from scientists who are researching what appears to be childhood cut short.

Dr. Sandra Steingraber in her report “The Falling Age of Puberty in U.S. Girls” writes, “In 1900, average U.S. menarcheal age , was 14.2 years.” Now, the mean age is 12.8.

“There is a fairly well-established link between early puberty and an increased risk for breast cancer,” says Williams, a breast cancer survivor herself. She says girls who reach puberty early are also at risk for sexual exploitation. “They’re little girls, but they have the appearance of teens, so they’re treated by the other gender as if they were teens, but they’re not.”

The reasons for early puberty are complex and interrelated. Obesity, racial and social disparities, not having been breastfed, being born too small or too early, and even the absence of a father can contribute to early puberty. But another factor, scientists say, is chemicals in the environment, specifically endocrine disruptors, which can mimic or block natural hormones in the body.

EDIT

http://www.newsreview.com/reno/Content?oid=692299

[sakabatou]

1. Yep

Environmental laws should be ignored, right *?

[ElectricGrid]

6. Who said that? You are losing it.

[sakabatou]

7. I should've used this:

:sarcasm:

[NV Whino]

2. I saw a pregnant young woman yesterday

She couldn't have been more than 12. I was stopped at a light so I got a good look at her--she was 14 tops, but I'm betting closer to 12. She was with her mother and younger brother (family resemblance was obvious). I almost cried.

[pansypoo53219]

3. hormones in food.

making boys equiptment smaller too. wait til it's proven to make males gay. THEN they might do something about it.

[happyslug]

4. This has more to do with the lack of Physically Activity than anything else.

In 1900, how did most people (including girls) get to school? They walked, even if it was a few miles away. How did most people get to the store? How did most people get to Church? How did most people visit friends? People, including girls, walked. Today most people hope in their car and drive (or if of the age in question, are driven). Furthermore more of the day to day work performed by most people were done manually, be it washing clothes or stacking hay. As people did less physical labor, the age of Menarche has declined. When studies have been done, the girls who are the most active physically, Menarche later then other girls of their own age.

Women athletic tend to Menarche much later than women who are NOT active. Women who are active physically (Even if NOT an athlete) also tend to Menarche later. My point is while other factors may be part of the problem, the single biggest factor is the reduction in physical activity of most people since 1900. There is strong evidence to support this as the major factor and all we need to do is increase the physical activity of most young Women (i.e. get them to walk to school, to their friends home, to the store, etc). If you increase the DAILY activity Menarche will occur later in their life.

[OKIsItJustMe]

5. Interesting data have been found regarding the absence of the genetic father in the home

http://www.springerlink.com/content/kyvf6mbul773enf9/

Father absence and age at menarche

A test of four evolutionary models

Journal Human Nature

Publisher	Springer New York
ISSN	1045-6767 (Print) 1936-4776 (Online)
Issue	Volume 14, Number 3 / September, 2003
DOI	10.1007/s12110-003-1004-2
Pages	209-233
SpringerLink Date	Friday, May 13, 2005

Sabine Hoier1 Contact Information
(1) Department of Psychology, University of Kassel FB 03, Holländische Straße 36-38, D-34127 Kassel, Germany

Received: 21 August 2002 Revised: 15 November 2002

Abstract Life history data, attractiveness ratings of male photographs, and attitudes towards partnership and child-rearing of 321 women were used to test four evolutionary models (quantitative reproductive strategy, male short-age, polygyny indication, and maternal reproductive interests) which attempt to explain the influence of family composition on reproductive strategies. Links between early menarche and other markers of reproductive strategy were investigated. Childhood stress and absence of a father figure, whether genetically related or not, were found to have accelerated menarche whereas having younger siblings decelerated it. Early menarche was associated with attractiveness ratings, the number of partners desired for the immediate future, and the early onset of intimate relationships. It was not linked with sociosexual orientation, mate choice criteria, and investment in the subjects’ own children, but these three markers were interrelated. The implications of the findings for the four evolutionary models are discussed.

...

However, endocrine disruption is scary. (Can you say "BPA?")
http://www.peoplespharmacy.com/archives/radio_shows/670_sex_hormone_disruption.php
http://www.peoplespharmacy.com/archives/radio_shows/671_hormone_disruption_part_2.php
http://www.pbs.org/moyers/journal/05232008/watch2.html