Puberty in a sample of Brazilian schoolgirls: timing and anthropometric characteristics

Abstract

Objective: The objective of this study was to determine the age at which puberty begins, age of menarche and anthropometric data of the participants at different stages of puberty. Subjects and me thods: This is a cross-sectional study in which we evaluated 665 girls, a sample representing the female schoolchildren population in Uberaba. Results: We found that thelarche, pubarche, underarm hair and menarche were attained at the age of 9.8 ± 1.4, 10.2 ± 1.4, 10.5 ± 1.5 and 11.7 ± 1.3 years, respectively. The mean interval between thelarche and menarche (ITM) was 1.7 ± 1.3 years. The prevalence of overweight and obesity was 31.3% and 95% of the participants began at thelarche between the age of 7 and 12 years. Conclusion: These values indicate a secular tendency to the decrease of the age of menarche and an earlier start of puberty. It is very important to understand these parameters to establish public policies aimed at plans to prevent these early events, especially regarding control of the prevalence of obesity. Arch Endocrinol Metab. 2015;59(2):105-11

Prevalence of overweight and obesity and associated factors in school children and adolescents in a medium-sized Brazilian city

“…The study cohort was chosen from a population of 48,390 (according to the 2009 census) primary and secondary children enrolled in public and private schools in Uberaba. The sample size calculation was performed in 3 steps 9 . First, a simple random sampling of the population was performed.…”

“…A total of 889 students (85%) attended public schools, and 157 (15%) attended private schools. The third step was achieved through a conglomerate sampling technique to establish the numbers of public and private schools (sample units) to be sampled to obtain the previous sample size calculation 9 , 10 .…”

“…The time spent watching TV, playing video games or using a computer (denominated sedentary leisure activities) was reported on the semi-structured questionnaire. The study participants, along with their parents or guardians, completed the pubertal development assessment 9 . They specified their current stage via photos representing the various pubertal phases proposed by Marshal and Tanner 16 and adapted by Chipkevitch 17 .…”

Epidemiology of Abdominal Obesity

“…However, some longitudinal studies demonstrated that childhood obesity is the trigger to early pubertal development because of increased exposure to reproductive steroids [estradiol level] [30,32,[34][35][36]. Furthermore, many genetic variants associated with the timing of menarche are in or near genes associated with childhood and adulthood obesity, so this fact should be considered [32].…”

RNA-seq analysis of lncRNA-controlled developmental gene expression during puberty in goat & rat

“…Puberty is a transitional stage for an animal from the immature sexual state to the mature sexual state, and it marks the onset of reproductive capability [ 1 ]. Puberty is well known to be controlled by a range of complex factors and their interactions, including genetic, metabolic, neuroendocrine, nutritional, and environmental factors [ 2 ].…”