M.E. Herman-Giddens, J. Steffes, S. Dowshen, M. Hussey, D. Harris, R. Wasserman, E. Slora, J. Serwint, D. Abney, L. Smitherman, E. Reiter.. Department of Maternal and Child Health, University of North Carolina School of Public Health, Chapel Hill, NC; Pediatric Research in Office Settings (PROS), American Academy of Pediatrics, Elk Grove Village, IL; Alfred I. duPont Hospital for Children, Wilmington, DE; Department of Biostatistics, Gillings School of Global Public Health, University of North Carolina, Chapel Hill, NC; Department of Pediatrics, University of Vermont, Burlington, VT; Continuity Research Network (CORNET), The Academic Pediatric Association, Mc Lean, VA; National Medical Association's Pediatric Network (NMAPedsNet), The National Medical Association, McLean, VA; Department of Pediatrics, Baystate Children's Hospital, Tufts University School of Medicine, Springfield, MA.
Presented at the May 2010 Pediatric Academic Societies Annual Meeting.
Background: Current data do not exist on the age of onset of pubertal characteristics for US boys. Past studies are limited by the time of the study, small sample sizes, lack of racial and ethnic diversity, nonstandardized methodology, and late age at enrollment. Heath professionals and the public have been calling for timely data for clinical use and for examining trends.
Objective: Estimate the current prevalence and mean ages of onset of pubertal characteristics in non-Hispanic white boys seen in pediatric practices from a larger ongoing study.
Design/Methods: Boys 6 through 16 years of age seen for well child examinations were recruited from 91 practices (90 in 37 states and 1 in Quebec) enrolled in one of three practice-based research networks: the Pediatric Research in Office Settings (PROS), the National Medical Association's Pediatric Network (NMAPedsNet) or the Continuity Research Network (CORNET). Practices were urban, non-inner city (28.8%), suburban (40.8%), rural (17.6%), and urban, inner city (10.4%). After standardized training and establishing inter-rater reliability of assessment, clinicians rated the level of sexual maturation for selected pubertal characteristics by age.
Results: Preliminary data were analyzed on 1,366 non-Hispanic white boys without chronic diseases or chronic medication use. At age 6, 8.33% were Tanner stage 2 for genitalia and 0.76% had pubic hair. At 10 years of age, proportions had increased to 35.71% and 25.00% respectively. Mean age of onset of genital growth was 10.39 years (95% CI: 10.18, 10.60), and 11.59 years for onset of pubic hair (95% CI: 11.42, 11.77). Mean age of onset of sexual maturity stage 5 was reached at age 15.63 (95% CI: 15.43, 15.82) for genitalia and 15.91 (95% CI: 15.70, 16.11) for pubic hair.
Conclusions: These data suggest that non-Hispanic white boys may be developing pubertal characteristics earlier than shown in previous studies. However, assessing secular trends presents challenges since few previous studies are available and none are exactly comparable. At the study's completion, the description of onset of increasing testicular volume, along with other pubertal characteristics will provide the largest and most current body of pubertal data on boys in the US.