Principal investigator: Mary L. Hediger, Ph.D.
There are two objectives of these analyses of stored biologic specimens (serum) for children, ages 6 to 11 years, who were examined as part of the Third National Health and Nutrition Examination Survey (NHANES III), between 1988 and 1994:

• To estimate, by assay of hormones (luteinizing hormone [LH] and inhibin B for boys and girls, testosterone for boys), the timing of the onset of pubertal development in a nationally representative sample of children, ages 6 to 11 years, and the concordance between hormonal indicators and pubertal onset based on physical maturation (based on Tanner sexual maturation scores) for children now ages 8 to 11 years. These findings will provide a baseline for determining pubertal status in earlier and subsequent surveys (NHANES and others) for which physical examination data are not available, which will enable researchers to determine whether there has been a secular decline in the age at the onset of puberty, as has been suggested based on physical examination (based on Tanner sexual maturation scores) in studies from NHANES III and other national studies.
• For girls: To determine if the recent findings from NHANES III girls, ages 8 to 18 years, that link blood lead (Pb) levels and delayed maturation based on Tanner scores (pubic hair) and age at menarche can be confirmed by hormonal analysis and extended to girls of younger ages. For boys: To determine if there are effects of blood Pb levels on timing of maturation, and in particular if higher blood Pb levels are associated with elevated levels (overproduction) of inhibin B, possibly indicating that spermatogenesis is compromised, as it is in adults with significant lead exposure.

Collaborators

· Germaine M. Buck Louis, Ph.D., M.S. (DESPR)
· John H. Himes, Ph.D. (Epidemiology and Community Health, University of Minnesota)
· Peter A. Lee, M.D., Ph.D. (Department of Pediatrics, Penn State College of Medicine)

Selected Publications

Wu T, Buck GM, & Mendola P. (2003). Blood lead levels and sexual maturation in U.S. girls: The Third National Health and Nutrition Examination Survey, 1988-1994. Environmental Health Perspectives, 111:737-741. [Abstract]

Hediger ML, Overpeck MD, McGlynn A, Kuczmarski RJ, Maurer KR, & Davis WW. (1999). Growth and fatness at three to six years of age of children born small- or large-for- gestational age. Pediatrics, 104(3):e33. [Abstract]