BMI relationship to the onset of puberty: assessment of growth parameters and sexual maturity changes in Egyptian children and adolescents of both sexes

Background: Puberty is the period of human growth and development. To determine the onset of puberty with regards to the effect of higher adiposity, together with growth parameters of the participants at various stages of sexual maturity for both sexes. Methods: The study was conducted on 1944 children (8-16) years; 1022 girls (52.6%) and 922 boys (47.4%) were taken at random. Pubertal assessment was done using Tanner staging that assigned breast development in females and pubic and axillary hair in males and females. Testicular volume was recorded using a Prader orchidometer. Height, weight, body mass index (BMI), body mass (BM) fat, body fat percentage, through applying a body impedance analyzer, and others were recorded. Results: The mean ages at the onset of puberty for females and males in our study were 10.29 +/- 1.1 and 11.34 +/- 1.02 years, respectively. Pubic hair (stage PH2) was attained at mean age of 10.72 +/- 0.84 and 11.98 +/- 1.03 years for females and males, respectively. For axillary hair (stage AH2), the mean age was 12.47 +/- 0.68 years for females and 13.8 +/- 0.58 years for males. The mean age at menarche was 12.41 +/- 0.65 years. In concordance to BM fat and percentage, all pubertal stages started earlier in females with BMI >= 85th percentile comparable to females within average BMI. As for males, no significant relation was noted between mean pubertal ages and BMI values. Conclusions: A significant association of mean ages of Tanner stages to excess weight especially in females warranted the increasing awareness about health care, nutritional aspects, and living circumstances.