age of puberty females
In addition to the increased risk for breast cancer as a result of earlier puberty onset, and the other effects of chemical contaminants on human development, Steingraber makes clear in her assessment that there are also many social reasons why we should be concerned about the declining age of puberty. While one may argue that as puberty declines, we may need to separate our notions of “childhood” from physiological development (an 8-year-old with breasts is no less a child than an 8-year-old who has not yet developed), society nevertheless projects a multitude of pressures on young girls who mature at an early age. One day last year when her daughter, Ainsley, was 9, Tracee Sioux pulled her out of her elementary school in Fort Collins, Colo., and drove her an hour south, to Longmont, in hopes of finding a satisfying reason that Ainsley began growing pubic hair at age 6. Ainsley was the tallest child in her third-grade class. Those who start puberty soonest aren't always the first to finish. In the Herman-Giddens study, the average age of full sexual maturity for boys of all races and ethnicities was about the same -- late in the 15th year. About a third of these boys reached full maturity two years sooner. Family stress can disrupt puberty timing as well. Girls who from an early age grow up in homes without their biological fathers are twice as likely to go into puberty younger as girls who grow up with both parents. Some studies show that the presence of a stepfather in the house also correlates with early puberty. As Steingraber concludes, “It is now the opinion of most endocrinologists...that the falling age of puberty among US girls is a real and ongoing phenomenon.” What is not as clear is why this is happening, and what (or if something) needs to be done about it. By Kathleen O’Grady. Many of us have heard the anecdotal evidence and may even know someone—a neighbour, a niece, a daughter: girls with breast buds and pubic hair at age 6 or 7 and first menstruation for 8-year-olds becoming the norm, not the exception. Reviewed by Brunilda Nazario, MD. Oct. 20, 2012 -- American boys are starting puberty up to two years earlier than decades ago, new data show. Boys are entering puberty at an average age of 10 among whites and Hispanics, and at an average age of 9 among African-Americans. About a third of boys start to mature sexually up to two years earlier than average. The findings come from a study of 4,131 boys examined at doctors' offices across the U.S. by Marcia Herman-Giddens, DrPH, and colleagues. The same team found a year-earlier shift in first puberty for girls. (Eight used to be the age cutoff for normal pubic-hair growth in girls; now it’s as early as 7.) For this girl, Greenspan prescribed a once-a-month shot of the hormone Leuprolide, to halt puberty’s progress. The girl hated the shot. Puberty, in girls, involves three events: the growth of breasts, the growth of pubic hair and a first period. Typically the changes unfold in that order, and the proc­ess takes about two years. But the data show a confounding pattern.
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