Girls as young as 7 hitting puberty

Females appear to be hitting puberty earlier, perhaps due to rising obesity rates and common chemicals found in plastic, a new study suggests.
Among 1,200 girls in the study, 15 per cent showed signs of breast development at age seven, which is between a year and four years earlier than what was considered usual.
The research, which was led by a team from Ohio, also suggests that puberty is arriving at increasingly younger ages.
Other key findings show that by the age of eight, 18 per cent of white girls and 42 per cent of black girls had developed breasts.
Those numbers suggest that girls at age seven or eight are twice as likely to have breasts as compared to girls a decade ago.
A 1997 study showed that only five per cent of white girls had breast development at age seven.
The new study, published on Monday, was printed in the medical journal Pediatrics, and it raises more concerns about how girls will deal with such developmental pressures.
Researcher Dr. Frank Biro said that partially developed bodies may push girls into behaviours they may not be emotionally and mentally ready for.
"Simply because one is physically more mature does not mean they are socially more mature or psychologically mature," he said.
Perhaps equally troubling are links between early sexual development and the risk of developing breast and endometrial cancers later in life. It appears that longer exposure to certain hormones exacerbates the risk of such cancers.
Unplanned pregnancies and exposure to sexually transmitted infections are also major concerns.
Other studies have shown that girls who develop earlier are also more likely to suffer through depression and self-esteem problems as they grow older.
While heavier girls seem to hit puberty earlier in life, the study suggests that environmental factors are also speeding up the process. Chemicals such as bisphenol A, which is commonly found in plastic, have been blamed for the early development.
Other compounds, like phthalates, appear to disrupt the normal work of hormones in the body.
Of interest is that in different U.S. cities, the onset of puberty appears to differ. In San Francisco, 11.6 per cent of seven-year-olds showed breast development.
By contrast, 18.9 per cent of seven-year-old girls in Cincinnati showed pubertal growth.