Abstract
Aim: A recent secular trend towards earlier thelarche has been suggested. The aim of this study is to examine normative ages of thelarche and menarche in contemporary US females. Methods: Trained physicians documented Tanner breast stage by observation in a cross-sectional cohort. Age of menarche was self-reported. The subjects were healthy female children and adolescents. The mean age of thelarche was determined by probit analysis and the mean age of menarche was determined by using a normal time-to-event model. Results: Mean age of thelarche was 9.7 years among 610 females aged 3.0-17.9 years (70% non-Hispanic Caucasian (NHC), 14% African-Americans, 7% Hispanic, 9% "other"). The mean age of menarche was 12.8 years for NHC, with African-Americans having menarche 0.6 years earlier. Conclusions: Thelarche occurred earlier than recently reported, while age of menarche remained unchanged, this supported a persistent secular trend towards earlier thelarche but stable age of menarche. This suggests that the observed thelarche is gonadotropin-independent or the tempo of pubertal advancement has slowed.
Original language | English (US) |
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Pages (from-to) | 47-51 |
Number of pages | 5 |
Journal | Journal of Pediatric Endocrinology and Metabolism |
Volume | 27 |
Issue number | 1-2 |
DOIs | |
State | Published - Jan 2014 |
All Science Journal Classification (ASJC) codes
- Pediatrics, Perinatology, and Child Health
- Endocrinology, Diabetes and Metabolism
- Endocrinology