Secondary Sexual Characteristics and Menses
in Young Girls Seen in Office Practice:
A Study from the Pediatric Research in Office Settings Network.

Pediatrics v.99, n.4, Apr97

Received Jan 23, 1996; accepted May 6, 1996.

From the ^* Department of Maternal and Child Health, School of Public Health and the Office of Chief Medical Examiner, University of North Carolina, Chapel Hill, North Carolina; ‡ Pediatric Research in Office Settings, Department of Research, American Academy of Pediatrics, Elk Grove Village, Illinois; the ^§ Department of Pediatrics, University of Vermont College of Medicine, Burlington, Vermont; the † Department of Pediatrics, University of Puerto Rico School of Medicine, San Juan, Puerto Rico; and the ^¶ Department of Biostatistics, School of Public Health, University of North Carolina, Chapel Hill, North Carolina.

Objective.  To determine the current prevalence and mean ages of onset of pubertal characteristics in young girls seen in pediatric practices in the United States.

Methods.  A cross-sectional study was conducted by 225 clinicians in pediatric practices belonging to Pediatric Research in Office Settings, a practice-based research network. After standardized training in the assessment of pubertal maturation, practitioners rated the level of sexual maturation on girls 3 through 12 years who were undergoing complete physical examinations.

Results.  Data were analyzed for 17 077 girls, of whom 9.6% were African-American and 90.4% white. At age 3, 3% of African-American girls and 1% of white girls showed breast and/or pubic hair development, with proportions increasing to 27.2% and 6.7%, respectively, at 7 years of age. At age 8, 48.3% of African-American girls and 14.7% of white girls had begun development. At every age for each characteristic, African-American girls were more advanced than white girls. The mean ages of onset of breast development for African-American and white girls were 8.87 years (SD, 1.93) and 9.96 years (SD, 1.82), respectively; and for pubic hair development, 8.78 years (SD, 2.00) and 10.51 years (SD, 1.67), respectively. Menses occurred at 12.16 years (SD, 1.21) in African-American girls and 12.88 years (SD, 1.20) of age in white girls.

Conclusions.  These data suggest that girls seen in a sample of pediatric practices from across the United States are developing pubertal characteristics at younger ages than currently used norms. Practitioners may need to revise their criteria for referral of girls with precocious puberty, with attention to racial differences.