In late 2000 and early 2001, the New York Times carried three articles about aspects of the debate over early puberty in American girls, The first was an article in the New York Times Magazine by Lisa Belkin on 24 December 2000, "The Making of an 8-Year-Old Woman" [available on an independent web page]. The following two were both written by science reporter Gina Kolata: Doubters Fault Theory Finding Earlier Puberty (20 February 2001) and 2 Endocrinology Groups Raise Doubt on Earlier Onset of Girls' Puberty (3 March 2001).

Belkin's article puts a human face on the landmark paper by Marcia Herman-Giddens and colleagues that reports sexual development is occurring earlier in American girls than in the past. In particular, Belkin explors a diversity of plausible causes that scientists have identified as possibly contributing to shifts in the timing of sexual development, including hormones in milk, contamination in food, increases in obesity, and social factors, including family circumstances that might cause stress.

Belkin quotes one researcher, Bruce Ellis: "It appears that the quality of the father-daughter relationship is the most important aspect of early family environment in relationship to subsequent puberty." Ellis goes on to say that the "absence of a biological father in a daughter's early life is associated with early puberty and that thte presence of an unrelated male in a household, no matter how consistent, may speed it even more." Belkin also interviews scientists studying the possible involvement of obesity. Other possible causes, including contamination, receive less attention.

What Belkin's article does not do, however, is challenge Herman-Giddens' original result. In contrast, Kolata's two articles raise issues both about the reliability of Herman-Giddens' finding and the use of them in medical practice.

The principal focus of her writing is on the latter: whether pediatric standards should be changed to regard earlier development as "normal." Both articles are based principally upon exchanges in the medical literature, in particular two letters published by groups of Pediatrics, the first (October 1999) recommending a change in standards of what is considered normal timing in development, and then a second letter (September 2000) challenging that recommendation.

In their October 1999 letter, Kaplowitz et al. recommended that pediatricians redefine the normal age range of puberty downward to reflect Herman-Giddens' findings: They conclude that (1) the prior standard that breast development before age 8 is precocious is based on outdated studies and (2) that instead of evaluating girls if they show either breast development or pubic hair by age 8 or earlier, this age be lowered to 7.

Herman-Giddens et al., it should be noted, did not propose to change the standards, but instead were more concerned about what factors--environmental or sociological--might be causing the change. They regarded the change as anything but normal. Their paper discusses several possible causes of the trend, such as contamination and obesity, none of which could be construed as "normal" nor a reason to ignore early development. If anything, Herman-Giddens shines a spotlight on the need to find out what is happening.

In the second letter (September 2000), Rosenfield et al. focus on two concerns: First, they argue that it is "premature to conclude that the normal age of puberty is occurring earlier." Second, they point to methodological problems in Herman-Giddens et al. that weaken the strengths of its conclusions. Their first point is not directed at Herman-Giddens but instead at what Kaplowitz et al. recommend to do about it. They are particularly concerned that a change in what is expected as normal would lead some young girls to not be evaluated (and possibly treated) if they were showing signs of early puberty at the age of 7-8. This is a legitimate concern, in agreement with Herman-Giddens but directly in contradiction to Kaplowitz et al.

With respect to methodological weaknesses in Herman-Giddens et al., Rosenfield et al. observe that the 17,000 children in the study were not randomly chosen but instead children brought to see pediatricians, some for illnesses, some for normal check-ups. Herman-Giddens et al. respond to this criticism in a reply in the same issue of Pediatrics that "the large number of girls in their study would make it unlikely that they were different from the population as a whole." They also acknowledge the value of replicating their work with an unquestionably representative sample of comparable size. They also comment "we agree that puberty at an early age may not be "normal" even though a large proportion of girls are experiencing it because factors that may be contributing are not yet understood."

To an observer of this debate, two things would appear obvious:

• getting at the causes of why such a significant percentage of young girls are showing signs of sexual development by age 7-8 is an important issue, whether or not the average age of puberty has changed.

• changing standards for what is considered "normal" in the pattern of sexual development is at best premature. Not only would make it likely that young girls might not receive needed medical attention but it would also discourage a larger investigation of why, if the age of puberty has changed, this is happening.

What factors affect the rate of sexual development?

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