Yahoo! News News Home - Yahoo! - My Yahoo! - News Alerts - Help

Reuters Media
Home  Top Stories  Business  Tech  Politics  World  Local  Entertainment  Sports  Op/Ed  Science   Health   Full Coverage
Health - Reuters - updated 5:33 PM ET Sep 13
My Add to My Yahoo!
Reuters  |  AP  |  |  HealthSCOUT  |  Yahoo! Health  |  Videos  

Thursday September 13 5:32 PM ET

US Boys May Be Hitting Puberty Sooner: Report

NEW YORK (Reuters Health) - Recent research has shown girls in the US may be starting puberty at an earlier age than in generations past, and a new study now suggests the same is true of boys.

Looking at data on more than 2,100 US boys and teens, researchers found evidence that males growing up in the 1980s and 1990s reached puberty sooner than those growing up in earlier years.

And African-American boys appeared to begin sexual development earlier than either whites or Mexican Americans did, according to findings reported in the September issue of the Archives of Pediatrics and Adolescent Medicine.

Dr. Marcia E. Herman-Giddens of the University of North Carolina at Chapel Hill--who, with her colleagues, reported the first evidence that US girls are maturing at ever more tender ages--led the new study on boys.

The researchers used data from a national health and nutrition survey collected between 1988 and 1994. They looked at the onset of pubic hair growth and genital maturation among 2,114 males aged 8 to 19.

The team found that, on average, white boys showed pubic hair development at age 12, Mexican American boys just past age 12 and black boys just beyond age 11. And African Americans were age 9.5, on average, when they showed testicle growth and other signs of genital maturation. White and Mexican-American boys were just past their 10th birthdays.

Overall, Herman-Giddens said, these boys began maturing at a younger age compared with boys in studies past. In a statement, she said the findings suggest US boys are now beginning puberty up to 6 months sooner. This echoes the findings from her 1997 study showing US girls--especially African Americans--may be maturing earlier than in the past.

Whether this trend is real, and what such early maturation means, is unclear. Herman-Giddens has speculated that US kids' high-fat, low-fiber diets and lack of exercise might be leading to body-fat changes that affect puberty onset--or that exposure to environmental chemicals that affect hormonal function could play a role.

The long-term health ramifications of early puberty, if any, are also unknown.

But in the statement, Herman-Giddens pointed out the major questions she believes this new study raises: ``Is this real, and is it healthy or not?''

``It's probably not healthy,'' she said, ``since earlier studies have shown that the sooner a boy starts puberty, the higher his risk is of developing testicular cancer, just as early-maturing girls are at greater risk of developing breast cancer.''

Also unclear is why African-American boys seem to be maturing particularly early, according to Herman-Giddens and her colleagues. They speculate that differences in anything from metabolism and hormone function to diet and environmental exposures may play a role.

An editorial accompanying the report notes the ``dramatic difference'' in puberty onset found in this study compared with previous ones.

Most evidence indicates that boys should begin genital maturation by age 14, according to Dr. Edward O. Reiter of Tufts University in Boston, Massachusetts, and Dr. Peter A. Lee of Hershey, Pennsylvania.

But based on these findings, the editorialists note, anywhere from 27% to 38% of US boys hit this milestone at age 8.

``These data are strikingly different from earlier studies in which as few as 0.62%...achieved this level of development,'' Reiter and Lee write.

However, they point out, ``because genital staging is so subjective, it must be questioned whether the authors used the same criteria as have been used traditionally.''

And, they note, the fact that pubic hair and genital growth are occurring does not mean a child has truly hit puberty. According to Reiter and Lee, there is no evidence kids are completing puberty earlier.

SOURCE: Archives of Pediatrics and Adolescent Medicine 2001;155:988-989,

Email this story - View most popular  |  Printer-friendly format

Archived Stories by Date:

News Resources
Message Boards: Post/Read Msgs
Conversations: Start a live discussion

 Weekly Specials

Search News
Search:  Stories   Photos   Audio/Video   Full Coverage
Home  Top Stories  Business  Tech  Politics  World  Local  Entertainment  Sports  Op/Ed  Science   Health   Full Coverage

Copyright 2001 Reuters Limited. All rights reserved. Republication or redistribution of Reuters content is expressly prohibited without the prior written consent of Reuters. Reuters shall not be liable for any errors or delays in the content, or for any actions taken in reliance thereon.
Copyright 2001 Yahoo! Inc. All rights reserved.
Questions or Comments
Privacy Policy - Terms of Service