Article

The physiology and timing of male puberty

Department of Growth and Reproduction, Rigshospitalet, University of Copenhagen, Denmark.
Current opinion in endocrinology, diabetes, and obesity (Impact Factor: 3.77). 04/2012; 19(3):197-203. DOI: 10.1097/MED.0b013e3283535614
Source: PubMed

ABSTRACT To describe available markers of male puberty, discuss associations between adiposity and pubertal timing and to review recent evidence of a possible secular trend in male pubertal timing.
An expert panel reviewing existing American pubertal data from boys in 2005 could not confirm a secular trend in male pubertal timing. National Health and Nutrition Examination Survey III findings have been confirmed by the National Institute of Child Health and Human Development study reporting a mean age of 10.4 years for Caucasian boys entering Tanner stage G2. Furthermore, the Copenhagen Puberty Study reported a 3 months decline in pubertal onset during a 15-year period (from 11.92 years in 1991 to 11.66 years in 2008).A negative association between obesity and early puberty was found in the National Institute of Child Health and Human Development study, in contrast to the positive association found in a Danish study. Other studies have not been able to document an association between prepubertal BMI and age at pubertal onset.
Evaluation of Tanner stage and especially assessment of testicular volume should both be used in epidemiological studies. We speculate that the association between fat mass and pubertal timing may be nonlinear and recent studies may indicate a small decline in age at pubertal onset in boys.

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    • "The past decades age at sexual maturation has declined, evident by a gradual younger age at menarche [20] [21] and breast development [22] among girls, and earlier testicular development in boys [23]. The obesity epidemic is thought to affect timing of pubertal development, and the process of pubertal development is a critical period for body composition development [24], but the association between obesity and pubertal development is far from clear [19]. Consequently, taken the increasing obesity epidemics into consideration, this urges us to learn more about of the process of pubertal development and metabolism, and metabolomics may be a useful tool. "
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    • "In girls, more than in boys, the change in pubertal age has been intriguing; in the last decades, the rate of precocious sexual maturation in girls has been high and increasing, and the mechanism for the 'epidemic' has been much debated, pointing fingers at toxins and perhaps other chemical products. Evidence that the timing of boys' somatic maturation is changing has recently been reviewed and remains inconclusive [3], though one Danish study documented a 3-month acceleration in male pubertal onset across a 15-year period (from 11.92 years in 1991 to 11.66 years in 2008) [4]. "
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