Author Affiliations: Medical Students Research Center, School of Medicine, Isfahan University of Medical Sciences, Isfahan, Iran (Kashani HH, Kavosh MS, Keshteli AH); School of Medicine, Iran University of Medical Sciences, Tehran, Iran (Montazer M); Isfahan Endocrine & Metabolism Research Center, Isfahan University of Medical Sciences, Isfahan, Iran (Rostampour N, Memar-Ardestani P, Abdeyazdan Z, Hashemipour M); Isfahan Cardiovascular Research Center, Isfahan University of Medical Sciences, Isfahan, Iran (Kelishadi R); Department of Biostatistics, Faculty of Health, Isfahan University of Medical Sciences, Isfahan, Iran (Shariatnejad K, Hosseini SM)

Corresponding Author: Mahin Hashemipour, MD, Professor of Pediatric Endocrinology, Isfahan Endocrine & Metabolism Research Center, Isfahan University of Medical Sciences, Sedigheh Tahereh Research Center, Khorram Street, Jomhouri Square, Isfahan, 81876-98191, Iran (Tel: +98 (311) 3359933; Fax: +98 (311) 3373733; Email: hashemipour@med.mui.ac.ir)

doi:10.1007/s12519-009-0026-1

Background: To obtain normal references for growth and pubertal development in a given population, assessment of pubertal stages is of great importance. This study aimed to determine the age of appearance of secondary sexual characteristics in a representative sample of Iranian girls.

Methods: This cross-sectional study was conducted during 2005-2006 in 3192 girl students, aged 6-17 years, in Isfahan, Iran. Participants were selected by multistage random cluster sampling from school students. Secondary sexual characteristics were evaluated by inspection and palpation, and were recorded according to Tanner staging. The self-reported date of menarche (if any) was recorded as well. Data were analyzed with Probit analysis based on the status quo method.

Results: The median ages (10th-90th percentile) of Tanner stage 2 breast development (B2) and Tanner stage 2 pubic hair growth (PH2) were 10.14 years (8.33-11.95 years) and 10.78 years (9.09-12.48 years), respectively. The ages of the 3rd percentile for B2 and PH2 were 7.48 and 8.29 years, respectively. The median age of menarche among the 3192 girls who had experienced menarche was 12.65 years (11.18-14.11 years).

Conclusions: The median age of puberty onset is 10.14 years, and the onset of puberty before 7.5 years is considered as precocious puberty in a representative sample of Iranian girls. The values obtained from the present study can provide baseline data for analysis of time trends, as well as for international comparisons.

Key words: menarche; precocious; pubarche; puberty; secondary sexual characteristics; telarche

                  World J Pediatr 2009;5(2):132-135