Secondary Sexual Characteristics and Menses in Young Girls

Abstract

To the Editor. The study by Herman-Giddens and associates on “Secondary Sexual Characteristics and Menses in Young Girls seen in Office Practice” in the April 1997 issue is a welcome addition to normative data on the growth of children in this country.1 It illustrates the importance of developing normative data from all racial groups. It is also a good example of the types of studies that can be done by combining samples from many different practice settings. Our general pediatric clinic has enrolled a large number of East African immigrant children as well as African-American children. We frequently see early onset of pubic hair and breast development in African-American and African girls in our practice. We have found that a careful evaluation of the genitalia, particularly for evidence of estrogenization of the hymen and labia,2 is very helpful for distinguishing this benign premature thelarche and adrenarche from true precocious puberty. Because we commonly find young girls with early development of pubic hair and breasts without any evidence of estrogenization of the hymen or labia, we do not think that estrogen is producing these premature physical changes. We doubt that exogenous estrogens in hair products are related to these changes as suggested in the article. Instead, it is likely that premature pubic hair and breast development are due to an early increase in androgen production by the adrenal gland and ovaries. Several studies have demonstrated higher mean androgen levels in girls with premature adrenarche and thelarche than in controls of the same age.3-8 In all studies levels overlap between subjects and controls. This suggests that there are genetically controlled differences in end organ sensitivity to androgens that produce the early pubic hair and breast development seen in African-American girls in the Herman-Giddens study. In our own practice we've …