SciELO - Scientific Electronic Library Online

vol.132 issue7DNA content and survival in subserous gallbladder carcinomaPsychological features and cognitive styles of students entering Medicine and other careers at the Pontificia Universidad Católica de Chile author indexsubject indexarticles search
Home Pagealphabetic serial listing  

Services on Demand




Related links


Revista médica de Chile

Print version ISSN 0034-9887


CODNER D, Ethel et al. Age of pubertal events in Chilean school age girls and its relationship with socioeconomic status and body mass index . Rev. méd. Chile [online]. 2004, vol.132, n.7, pp.801-808. ISSN 0034-9887.

Background: Recent studies in the United States have demonstrated that a significant proportion of girls show thelarche before the age of eight years. Nutritional status, geographic influences and racial factors are known to affect the timing of puberty. Aim: To evaluate the age of onset of puberty, development of secondary sexual characteristics and menarche in Chilean girls, and its relation to obesity and socioeconomic status. Material and methods: Healthy girls attending elementary school, from first to ninth grade in Santiago, Chile, were studied. A pediatric endocrinologist evaluated pubertal development using Tanner classification. Breast development was assessed by inspection and breast palpation. Average age of onset of pubertal events was determined by probit analysis. Results: A total of 758 girls, aged 5.8 to 16.1 years, were recruited. Obesity, defined as a BMI greater than 90th percentile, was found in 24.4%. The age of menarche was 12.7 years, the onset of Tanner stage 2 breast development and pubic hair was at 8.9 and 10.4 years, respectively. Sixteen percent of girls aged 7 to 7,9 years, had thelarche. Upper class girls showed a later onset of breast Tanner stage 4 stage than low-middle class girls. Obesity was not found in logistic regression analysis to be a significant predictive factor in the onset of puberty. Conclusions: The age of menarche has not changed in the last thirty years, but an earlier onset of thelarche has occurred. The high frequency of thelarche between 7 and 8 years suggests that the normal age of breast development should be revised (Rev Méd Chile 2004; 132: 801-8)

Keywords : Body mass index; Menarche; Puberty; Sex maturation.

        · text in Spanish     · Spanish ( pdf )


Creative Commons License All the contents of this journal, except where otherwise noted, is licensed under a Creative Commons Attribution License