2 Endocrinology Groups Raise Doubt on Earlier
Onset of Girls' Puberty

By GINA KOLATA

Two professional societies representing endocrinologists have issued a statement saying that despite the conclusion of a widely noted study, it is not yet established that girls typically enter puberty earlier today. The groups urged that girls who appear to be starting sexual development at a young age see a specialist as soon as possible.

The organizations, the Endocrine Society and the Lawson-Wilkins Pediatric Endocrine Society, also urged that rigorous studies be undertaken to determine not just the average age when puberty begins but how quickly it progresses.

They questioned the study concluding that puberty was starting earlier, saying that doctors and nurses who had evaluated girls might have mistaken fat tissue in chubby girls for breasts and that the girls in the study had not been randomly selected.

And, they said, the age of girls at the one incontrovertible sign of puberty  first menstruation  has been the same for decades.

"All recognize that the age at the first period, which I think is the most critical event, has not changed, which would suggest to me that the tempo of puberty has not changed," said Dr. Edward Reiter, president of the Lawson-Wilkins Pediatric Endocrine Society and a pediatric endocrinologist at Baystate Medical Center Children's Hospital in Massachusetts.

Dr. Benita Katzenellenbogen, president of the Endocrine Society and a professor at the University of Illinois, said she worried that serious medical conditions, like tumors and hormonal disorders, that can cause early sexual development might be missed if pediatricians simply assumed that it was normal for girls to start puberty at a very early age. "It really is an important issue," she said.

The new statement was applauded by some pediatric endocrinologists, who had been deeply concerned that the public and many pediatricians had decided that it was a settled fact that girls were now starting puberty as early as first grade and that there was no need to worry about such early sexual development.

That impression, they said, was generated by a study published in 1997 and then fueled by a separate paper, published in 1999 and endorsed by two subcommittees of the Lawson-Wilkins Pediatric Endocrine Society, saying that puberty was occurring earlier and that the guidelines for determining which girls needed to see specialists should be revised accordingly. (The Endocrine Society, which represents adult and pediatric endocrinologists alike, had never taken a position on the question.)

"This is definitely a retrenchment and a fallback to a more conservative position," said one leading critic of the earlier stance, Dr. Robert Rosenfield, a pediatric endocrinologist at the University of Chicago. "It shows that our concerns have been taken seriously," Dr. Rosenfield added.

Another critic, Dr. Laura K. Bachrach, a pediatrics professor at Stanford University, said, "I think it bodes to settle what was the equivalent of a civil war."

But Dr. Paul Kaplowitz, a principal author of the 1999 paper, declined to comment on whether the new statement was a retrenchment. Dr. Kaplowitz, a pediatric endocrinologist at the Medical College of Virginia of Virginia Commonwealth University, said instead: "I feel that the original study showing that puberty is occurring earlier is still valid. But I agree that additional studies need to be done to confirm this finding and to find out why girls are maturing earlier."

The notion that girls were entering puberty earlier got its start with the 1997 paper, published in the journal Pediatrics, on a study that involved more than 17,000 girls. The children, ages 3 to 12, were examined in their pediatricians' private offices.

The author, Dr. Marcia E. Herman-Giddens, a child health expert and adjunct professor at the University of North Carolina at Chapel Hill, concluded that black girls began developing breasts at an average age of 8.87 years and pubic hair at an average age of 8.78. For white girls, the average ages were 9.96 years for breasts and 10.51 for pubic hair. And, because the average ages for both those characteristics were lower than what textbooks suggested, the low end of the normal age range for puberty's onset was also pushed back statistically, to age 6 for black girls and age 7 for whites. But the average age at first menstruation  12.16 for black girls and 12.88 for whites  was about the same as the textbooks said.

In 1999, Dr. Kaplowitz and Dr. Sharon Oberfield, a pediatric endocrinologist at Columbia University's College of Physicians and Surgeons, published a paper calling for revised guidelines for assessing early puberty. On the basis of Dr. Herman-Giddens's data, they said that in general, black girls starting puberty at age 6 and white girls at age 7 would be considered normal. Most textbooks said girls who were starting sexual development before age 8 required medical evaluations for precocious puberty.

But Dr. Katzenellenbogen, president of the Endocrine Society, said yesterday that she and others did not consider Dr. Herman-Giddens's paper conclusive. Dr. Katzenellenbogen cited the way the study was done. For example, she said, "all the pubertal changes were based on visual inspections  no endocrine evaluations or hormonal measurements were done." In addition, she noted, "the subjects were not randomly selected," a factor that might have introduced bias into the results.

In response to similar criticism, Dr. Herman-Giddens has consistently defended her study.

Some pediatric endocrinologists said that while Dr. Kaplowitz and Dr. Oberfield had been careful to include caveats and nuances in their article calling for revised guidelines, the message that got out was to dismiss puberty in 6- and 7- year-old girls as normal.

As a result, said Dr. Reiter, president of the Lawson-Wilkins society, he worried that pediatricians were taking age 6 for black girls and age 7 for whites as "a magic number" for the onset of sexual development. These girls "need to be individually monitored, individually followed," he said, adding that doctors "should not be saying: `Don't worry about it. It's normal. See you at your next annual exam.' "