The physiology and timing of male puberty

Disruption of gonadotropin hormone biosynthesis by parabens: A potential development and reproduction-associated adverse outcome pathway

Parabens are widely used as antibacterial preservatives in foods and personal care products. The knowledge about the modes of toxic action of parabens on development and reproduction remain very limited. The present study attempted to establish a development and reproduction-associated adverse outcome pathway (AOP) by evaluating the effects of methylparaben (MP), ethylparaben (EP), propylparaben (PP) and butylparaben (BP) on the biosynthesis of gonadotropins, which are key hormones for development and reproduction. MP and BP significantly upregulated the mRNA and protein levels of follicle stimulating hormone (FSH) and luteinizing hormone (LH) in pituitary gonadotropic cells in a concentration-dependent manner. Activation of gonadotropin-releasing hormone receptor (GnRHR) was required for gonadotropin biosynthesis induced by BP, but not MP. Molecular docking data further demonstrated the higher binding efficiency of BP to human GnRHR than that of MP, suggesting GnRHR as a potential molecular initiative event (MIE) for BP-induced gonadotropin production. L-type voltage-gated calcium channels (VGCCs) were found to be another candidate for MIE in gonadotropic cells response to both MP and BP exposure. The calcium-dependent activation of extracellular signal-regulated kinase 1 (ERK1) and ERK2 was subsequently required for MP- and BP-induced activation of GnRHR and L-type VGCCs pathways. In summary, MP and BP promoted gonadotropin biosynthesis through their interactions with cellular macromolecules GnRHR, L-type VGCCs, and subsequent key event ERK1/2. This is the first study to report the direct interference of parabens with gonadotropin biosynthesis and establish a potential AOP based on pathway-specific mechanism, which contributes to the effective screening of environmental chemicals with developmental and reproductive health risks.

Cryptorchidism and puberty

Cryptorchidism is the condition in which one or both testes have not descended adequately into the scrotum. The congenital form of cryptorchidism is one of the most prevalent urogenital anomalies in male newborns. In the acquired form of cryptorchidism, the testis that was previously descended normally is no longer located in the scrotum. Cryptorchidism is associated with an increased risk of infertility and testicular germ cell tumors. However, data on pubertal progression are less well-established because of the limited number of studies. Here, we aim to review the currently available data on pubertal development in boys with a history of non-syndromic cryptorchidism-both congenital and acquired cryptorchidism. The review is focused on the timing of puberty, physical changes, testicular growth, and endocrine development during puberty. The available evidence demonstrated that the timing of the onset of puberty in boys with a history of congenital cryptorchidism does not differ from that of non-cryptorchid boys. Hypothalamic-pituitary-gonadal hormone measurements showed an impaired function or fewer Sertoli cells and/or germ cells among boys with a history of cryptorchidism, particularly with a history of bilateral cryptorchidism treated with orchiopexy. Leydig cell function is generally not affected in boys with a history of cryptorchidism. Data on pubertal development among boys with acquired cryptorchidism are lacking; therefore, more research is needed to investigate pubertal progression among such boys.

Enduring sex-dependent implications of pubertal stress on the gut-brain axis and mental health

The gut-brain axis (GBA) is a network responsible for the bidirectional communication between the central nervous system and the gastrointestinal tract. This multifaceted system is comprised of a complex microbiota, which may be altered by both intrinsic and extrinsic factors. During critical periods of development, these intrinsic and extrinsic factors can cause long-lasting sex-dependent changes in the GBA, which can affect brain structure and function. However, there is limited understanding of how the GBA is altered by stress and how it may be linked to the onset of mental illness during puberty. This article reviews current literature on the relationships between the GBA, the effects of stress during puberty, and the implications for mental health.

Time trends towards earlier puberty in boys and girls with type 1 diabetes: Insights from the German Diabetes Prospective Follow-up (DPV) registry, 2000 to 2021

AIM

To examine the time trends and factors associated with the onset of puberty in children with type 1 diabetes (T1D) using data from the German Diabetes Prospective Follow-up (Diabetes-Patienten-Verlaufsdokumentation [DPV]) registry.

METHODS

A total of 13 127 children with T1D, aged 6 to 18 years, were included in the analysis. Regression analysis was performed to investigate the relationship between diabetes duration, body mass index (BMI) standard deviation score (SDS), glycated haemoglobin (HbA1c) level, migration background, and the onset of puberty, stratified by sex.

RESULTS

Our findings revealed a significant trend towards earlier puberty in both girls and boys with T1D over the observed period (2000 to 2021). Puberty onset in girls (thelarche Tanner stage B2) decreased from 11.48 (11.35-11.65) years in 2000 to 10.93 (10.79-11.08) years in 2021 and gonadarche (Tanner stage G2/testicular volume >3 mL) decreased from 12.62 (12.42-12.82) years in 2000 to 11.98 (11.79-12.16) years in 2021 in boys (both P < 0.001). Longer diabetes duration, higher BMI SDS, and lower HbA1c level were associated with earlier puberty in both sexes (P < 0.001).

CONCLUSIONS

Our study highlights earlier puberty in children with T1D, influenced by BMI SDS, HbA1c level, and migration background. This has important implications for diabetes management and supporting healthy development. Further research is needed to understand the underlying mechanisms and develop potential interventions for this vulnerable population.

A Narrative Review of Flutamide in Juvenile Nasopharyngeal Angiofibroma

The detection of androgen receptors within Juvenile Nasopharyngeal Angiofibroma (JNA) has prompted investigation of the role of Flutamide. The aim of this review is to evaluate Flutamide as a possible neo-adjuvant treatment for JNA. Literature searches were conducted using MEDLINE, EMBASE and Web of Science. The Joanna Briggs Institute (JBI) checklist was used to assess risk of bias. The Oxford Centre of Evidence-Based Medicine (OCEBM) Levels of Evidence was used to stratify the evidence level. Literature searches were conducted using MEDLINE, EMBASE and Web of Science. Flutamide as neo-adjuvant treatment potentially causes a reduction in JNA tumor volume by ≥ 25%. Based on the current limited evidence, Flutamide has a limited role in JNA management and further research is required. Its utilization should only follow discussion with the patient, their families, and within the multidisciplinary team.

Father absence and pubertal timing in Korean boys and girls

Background and objectives

Pubertal timing is a key life history trait with long-term health consequences in both sexes. Evolutionary theory has guided extensive research on developmental influences, in particular growing up without a father, on earlier menarche. Far less is known whether a similar relationship exists for boys, especially beyond western contexts. We used longitudinal data from the nationally representative sample of Korean adolescents, which provided us with a unique opportunity for studying male puberty using a hitherto underutilized biomarker: age at first nocturnal ejaculation.

Methodology

We pre-registered and tested a prediction that growing up in father-absent households is associated with earlier puberty in both sexes. Large sample size (>6000) allowed testing the effect of father absence, which remains relatively uncommon in Korea, while adjusting for potential confounders using Cox proportional-hazard models.

Results

Self-reported age at first nocturnal ejaculation was on average 13.8 years, falling within the range known from other societies. Unlike previous findings mostly for white girls, we did not find evidence that Korean girls in father-absent households had a younger age at menarche. Boys in father-absent households reported having their first nocturnal ejaculation 3 months earlier on average, and the difference was evident before age 14.

Conclusion and implications

The association between father absence and pubertal timing appears sex- and age-dependent, and these differences may further interact with cultural norms regarding gender roles. Our study also highlights the utility of the recalled age of first ejaculation for male puberty research, which has lagged in both evolutionary biology and medicine.

Risk factors on testicular function in adolescents

PURPOSE

Adolescence represents an important window for gonadal development. The aim of this review is to carry out a critical excursus of the most recent literature on endogenous and exogenous risk factors related to testicular function, focusing the research on adolescence period.

METHODS

A comprehensive literature search within PubMed was performed to provide a summary of currently available evidence regarding the impact on adolescence of varicocele, cryptorchidism, cancer, diabetes, lifestyle factors, endocrine disruptors, obesity and sexually transmitted diseases. We focused on human studies that evaluated a possible impact of these factors on puberty timing and their effects on andrological health.

RESULTS

Evidence collected seems to suggest that andrological health in adolescence may be impaired by several factors, as varicocele, cryptorchidism, and childhood cancer. Despite an early diagnosis and treatment, many adolescents might still have symptoms and sign of a testicular dysfunction in their adult life and at the current time it is not possible to predict which of them will experience andrological problems. Lifestyle factors might have a role in these discrepancies. Most studies point out towards a correlation between obesity, insulin resistance, alcohol, smoking, use of illegal drugs and testicular function in pubertal boys. Also, endocrine disruptors and sexually transmitted diseases might contribute to impair reproductive health, but more studies in adolescents are needed.

CONCLUSION

According to currently available evidence, there is an emerging global adverse trend of high-risk and unhealthy behaviors in male adolescents. A significant proportion of young men with unsuspected and undiagnosed andrological disorders engage in behaviors that could impair testicular development and function, with an increased risk for later male infertility and/or hypogonadism during the adult life. Therefore, adolescence should be considered a key time for intervention and prevention of later andrological diseases.

Pubertal induction and transition to adult sex hormone replacement in patients with congenital pituitary or gonadal reproductive hormone deficiency: an Endo-ERN clinical practice guideline

An Endo-European Reference Network guideline initiative was launched including 16 clinicians experienced in endocrinology, pediatric and adult and 2 patient representatives. The guideline was endorsed by the European Society for Pediatric Endocrinology, the European Society for Endocrinology and the European Academy of Andrology. The aim was to create practice guidelines for clinical assessment and puberty induction in individuals with congenital pituitary or gonadal hormone deficiency. A systematic literature search was conducted, and the evidence was graded according to the Grading of Recommendations, Assessment, Development and Evaluation system. If the evidence was insufficient or lacking, then the conclusions were based on expert opinion. The guideline includes recommendations for puberty induction with oestrogen or testosterone. Publications on the induction of puberty with follicle-stimulation hormone and human chorionic gonadotrophin in hypogonadotropic hypogonadism are reviewed. Specific issues in individuals with Klinefelter syndrome or androgen insensitivity syndrome are considered. The expert panel recommends that pubertal induction or sex hormone replacement to sustain puberty should be cared for by a multidisciplinary team. Children with a known condition should be followed from the age of 8 years for girls and 9 years for boys. Puberty induction should be individualised but considered at 11 years in girls and 12 years in boys. Psychological aspects of puberty and fertility issues are especially important to address in individuals with sex development disorders or congenital pituitary deficiencies. The transition of these young adults highlights the importance of a multidisciplinary approach, to discuss both medical issues and social and psychological issues that arise in the context of these chronic conditions.

Early-Life Exposure to Environmental Contaminants Perturbs the Sperm Epigenome and Induces Negative Pregnancy Outcomes for Three Generations via the Paternal Lineage

Due to the grasshopper effect, the Arctic food chain in Canada is contaminated with persistent organic pollutants (POPs) of industrial origin, including polychlorinated biphenyls and organochlorine pesticides. Exposure to POPs may be a contributor to the greater incidence of poor fetal growth, placental abnormalities, stillbirths, congenital defects and shortened lifespan in the Inuit population compared to non-Aboriginal Canadians. Although maternal exposure to POPs is well established to harm pregnancy outcomes, paternal transmission of the effects of POPs is a possibility that has not been well investigated. We used a rat model to test the hypothesis that exposure to POPs during gestation and suckling leads to developmental defects that are transmitted to subsequent generations via the male lineage. Indeed, developmental exposure to an environmentally relevant Arctic POPs mixture impaired sperm quality and pregnancy outcomes across two subsequent, unexposed generations and altered sperm DNA methylation, some of which are also observed for two additional generations. Genes corresponding to the altered sperm methylome correspond to health problems encountered in the Inuit population. These findings demonstrate that the paternal methylome is sensitive to the environment and that some perturbations persist for at least two subsequent generations. In conclusion, although many factors influence health, paternal exposure to contaminants plays a heretofore-underappreciated role with sperm DNA methylation contributing to the molecular underpinnings involved.

Obesity in childhood: how to improve male adolescence incoming

INTRODUCTION

Earlier or delayed puberty can be determined by numerous causes, but the exact mechanisms are not fully known. Anyway, those may be independent from the hypothalamicpituitary-gonadal axis involvement. Certainly, obesity is one of the main factors. In fact, obesity and infertility are strongly linked. For this reason, we want to analyse the relationship between puberty and obesity and give an updated state-of-the-art starting by discussing a 14-year-old obese boy's clinical case.

EVIDENCE ACQUISITION

Literature data are conflicting. Main criticisms are related to study design and evaluation criteria. Indeed, examined populations are not homogeneous by age, Tanner stage and BMI classification. The obesity epidemic is involved in earlier puberty, and puberty seems to be anticipated in all BMI groups. Very few studies evaluate the level of adiposity in the diagnosis of obesity. However, the role of the adipose tissue is crucial for hormone synthesis and regulation. Therefore, fat mass age-related and not simply BMI has to be considered by clinicians for appropriate diagnosis.

EVIDENCE SYNTHESIS

Regarding the clinical case, in three months our patient recovered delayed pubertal development following an anti-inflammatory and antioxidant Mediterranean Diet. Loss of weight, as in decrease of fat mass but saving of lean mass, increased testicular volume and testosterone levels occurred.

CONCLUSIONS

Puberty depends on several factors, including obesity. Further studies are needed to evaluate age groups, Tanner stage, diet and lifestyle, ethnicity and above all the fat/lean mass ratio. Lack of adequate tools could hinder a clinician's ability to recognize when or if therapeutic intervention is needed.

The relationship between pubertal timing and under-nutrition in rural Pakistan

INTRODUCTION

Sexual development in females and males are routinely measured according to the Tanner Stages. Sparse data exist on the timing of pubertal milestones in Pakistan. To fill this gap, the age of attainment of pubertal milestones and their relationship with nutritional status was explored among children and adolescents living in the rural district of Matiari, Pakistan.

METHODS

Anthropometry, nutrition biomarkers and Tanner Stage were assessed among girls aged 9.0-14.9 years (n = 723) and boys aged 10.0-15.9 years (n = 662) who were free from known disease in the rural District of Matiari, Pakistan. Median age was calculated for all Tanner Stages and menarche. Multivariable linear regressions were undertaken to determine covariates associated with the timing (age) of pubertal milestones.

RESULTS

Among participants living in this rural community, the median age of puberty onset for girls was 11.9 years (95%CI:10.9; 12.5) and boys was 12.3 years (95%CI:11.5; 12.9). Age at first menarche was 12.9 years (95%CI:12.1; 13.3). Undernutrition was widespread among adolescents in this community. Thirty-seven percent of females and 27.0% of males were stunted while 20.5% of females and 31.3% of males were thin. Only 8% (n = 58) of females and 12% (n = 78) of males were free from any nutrient deficiency with most adolescents having two or three nutrient deficiencies.

CONCLUSIONS

Undernutrition (stunting or thinness) was associated with relatively older ages for early puberty stages but not puberty completion. This may decrease the duration of the pubertal growth spurt and curtail potential catch-up growth that may occur during puberty. Efforts to decrease nutrient deficiencies, stunting and thinness beyond childhood should be made in rural Pakistan.

The investigation of pharyngeal airway space by cephalogram landmarks in primary school children in Taiwan

Background/purpose

Proper breathing is essential to healthy growth and development of children. The present study aimed to investigate changes in the pharyngeal airway space in primary-school children.

Materials and methods

Cephalometric radiographs were obtained from 93 primary-school children, who were divided into three age groups (Group I, aged 7–8 years; Group II, aged 9–10 years; and Group III, aged 11–12 years). Landmarks identified on each cephalogram included the tip of the uvula (U), hyoid bone (H), and epiglottis (E). Linear and angular measurements comprised nasopharyngeal airway (NP); PS (shortest distance from the soft palate to the pharyngeal wall); UP (distance from the tip of the uvula to the pharyngeal wall); TS (shortest distance from the posterior tongue to the pharyngeal wall); EP (distance, parallel to the X-axis, from the epiglottis to the pharyngeal wall). Statistical analysis was performed using one-way analysis of variance and Pearson correlation tests.

Results

Group III had the highest values for all the variables. The three groups exhibited significant differences for all pharyngeal airway variables, except for EP. The three groups had significantly different vertical U, H, and E. There were positive correlations between age and NP, PS, UP, and TS; however, no significant correlation was observed between age and EP. Age significantly correlated with the vertical U, E, and H. Correlations between age and the horizontal U, E, and H were nonsignificant.

Conclusion

Among primary-school children from various grades, age significantly correlated with all pharyngeal airway variables, except with EP.

Revisiting the critical weight hypothesis for regulation of pubertal timing in boys

BACKGROUND

Recent findings indicate that there is a body weight-sensing homeostatic regulation of body weight in postpubertal rodents and humans. It is possible that body weight sensing also might be involved in the regulation of pubertal timing. Although an early small study suggested that there is a critical body weight for pubertal timing in girls, most studies have focused on BMI and reported an inverse association between BMI and pubertal timing.

OBJECTIVES

In the present longitudinal well-powered cohort study, we revisited the critical weight hypothesis and tested if prepubertal body weight is a more robust inverse predictor of pubertal timing than prepubertal BMI in boys.

METHOD

We included men born during 1945-1961 (old cohort; n = 31,971) and men born during 1981-1996 (recent cohort; n = 1465) in the large BMI Epidemiology Study (BEST) Gothenburg (combined BEST cohort n = 33,436). Men with information on prepubertal body weight and BMI at 8 y of age and age at peak height velocity (PHV; an objective measure of pubertal timing) were included.

RESULTS

Body weight explained more of the variance in age at PHV than BMI in both the old cohort and the recent cohort (combined cohort, body weight 6.3%, BMI 3.6%). Both body weight (β: -0.24 SD/SD increase in weight; 95% CI: -0.25, -0.23) and BMI (β: -0.18 SD/SD increase in BMI, 95% CI: -0.19, -0.17) were inversely associated with age at PHV but the association for body weight was significantly more pronounced than the association for BMI (P < 0.001).

CONCLUSIONS

In conclusion, prepubertal body weight is a more robust inverse predictor of pubertal timing than prepubertal BMI in boys. We propose that body weight sensing constitutes a feedback mechanism to regulate pubertal timing.

[Body phenotypes in adolescence: is it necessary to adjust body mass index according to sexual maturation stages?]

This study aimed to analyze the effect of sexual maturation on body phenotypes, based on multivariate analysis of adolescents' nutritional status. This was a cross-sectional study with a sample of 833 adolescent schoolchildren 10 to 15 years of age, selected by complex sampling in Piracicaba, São Paulo State, Brazil. Body phenotypes were defined by principal components analysis (PCA), based on age, anthropometric data (body mass, height, skinfolds, and waist circumference), body composition (phase angle measured by bioelectrical impedance), and biochemical parameters (triglycerides, glucose, total cholesterol/LDL ratio, hemoglobin). Body phenotypes were classified as: P1adiposity characterized as positive association with skinfolds, body mass, and waist circumference; P2growth characterized as positive association between height and age; P3biochemical characterized as positive association with total cholesterol/LDL ratio, triglycerides, and glucose; and P4metabolic characterized as positive association with phase angle and hemoglobin and negative association with glucose. The phenotypes were later considered outcomes in the mixed effects analysis, incorporating sex at the first level and sexual maturation, age, sex, and socioeconomic score at the second level. This analysis allowed measuring the effect of sexual maturation on body phenotypes. Our results indicate that sexual maturation only a displayed relevant explanation of body phenotype that represents linear growth (height and age). Thus, it is not necessary to adjust anthropometric measures by sexual maturation.

Timing of Pubertal Milestones in Low- and Middle-Income Countries: A Systematic Review and Meta-Analysis

Despite increasing global attention to adolescent health in low- and middle-income countries (LMICs), limited literature exists on the timing of pubertal development in these settings. This study aimed to determine the age at menarche (AAM) and age of puberty onset [female Tanner Stage Breast 2 (B2) and male Tanner Stage Genital 2 (G2)] among healthy adolescents living in LMICs. It also aimed to explore the impact of nutritional status on pubertal timing in this population. MEDLINE, Embase, Cochrane CENTRAL, Web of Science, Scopus, and grey literature databases were searched. Observational studies and control arms of randomized controlled trials (RCTs) with healthy participants from LMICs born in or after 1998 were included. Pooled estimates with 95% CIs were calculated by random-effects meta-analyses using the DerSimonian and Laird inverse variance method for each pubertal milestone and by BMI category subgroups. Twenty-seven studies were included in the meta-analysis, representing 90,188 adolescents (78.3% female). Pooled mean estimates for AAM for normal, thin, and overweight BMI groupings were 12.3 y (95% CI: 12.1, 12.5), 12.4 y (95% CI: 12.2, 12.6), and 12.1 y (95% CI: 11.7, 12.5), respectively. For Tanner Stage B2, pooled mean age estimates for normal, thin, and overweight BMI groupings were 10.4 y (95% CI: 9.2, 11.6), 10.2 y (95% CI: 9.3, 11.4), and 8.4 y (95% CI: 6.8, 10.0), respectively. Finally, for Tanner Stage G2, pooled mean estimates for normal, thin, and overweight BMI groupings were 11.0 y (95% CI: 10.3, 11.7), 11.3 y (95% CI: 9.8, 12.9), and 10.3 y (95% CI: 10.0, 10.6), respectively. Data on the timing of pubertal milestones has traditionally come from high-income settings. In this systematic review of contemporary data from adolescents in LMICs, AAM, as well as age at pubertal onset, were similar to those reported from high-income settings.

New insights into the association of mid-childhood macronutrient intake to pubertal development in adolescence using nutritional geometry

Nutritional geometry (NG) is a novel dietary analysis approach that considers nutrient balance, rather than single nutrient effects, on health and behaviour. Through NG, recent animal experiments have found that lifespan and reproduction are differentially altered by dietary macronutrient distribution. Epidemiological research using NG reports similar findings for human ageing. Yet, the relation of macronutrient balance to human reproduction, especially reproductive maturation, remains undefined. We studied the impact of childhood macronutrient intake on pubertal maturation, by applying NG to an Australian longitudinal adolescent dataset. Food records, collected at age 8 years from 142 pre-pubertal children (females, 92; males, 50), were analysed for absolute energy, percentage energy and energy-adjusted residuals from protein, carbohydrate and fat. Pubertal stage change (assessed at 8, 13 and 15 years) was modelled to obtain individual mathematical estimates of pubertal timing and tempo. Timing of menarche was recorded. The association of macronutrients to pubertal timing/tempo was assessed via NG, involving generalised additive models and heat maps to aid interpretation. Results showed lower dietary protein (relative to carbohydrate and fat) in girls consistently predicted earlier pubertal timing and menarche, and was related to faster pubertal tempo (all P < 0·05). No significant associations were identified in boys for both timing and tempo. Results suggest a role of non-protein macronutrients in facilitating female maturation; corroborating feeding and reproductive behaviour patterns observed in earlier NG studies of primates. Application of NG to other adolescent datasets is required to confirm the present findings. Such work would advance understanding of how nutrient balance shapes human development and health.

Later puberty onset among chronically undernourished adolescents living in a Karachi slum, Pakistan

AIM

To assess factors associated with the timing of puberty onset (Tanner Stage Breast 2/Genital 2) among adolescents living in an urban slum in Karachi, Pakistan.

METHODS

Girls enrolled at 8-10 years (n = 1009) and boys 9-11 years (n = 863) were followed every 6 months from 2006 to 2010. Parametric survival analysis for interval-censored data was used to estimate median age at puberty onset and assess the association between exposures and timing of puberty onset.

RESULTS

The overall median age at Tanner Stage Breast 2 (AAB2) was 10.1 years (95% CI: 10.1; 10.5), and the median age at Tanner Stage Genital 2 (AAG2) was 10.1 years (95% CI: 10.1; 10.6). Stunting delayed AAB2 1 year and AAG2 about 6 months when compared to non-stunted peers. In the multivariable model, after adjusting for age at enrolment, stunting, thinness and vitamin A deficiency (VAD) were significantly associated with delayed AAB2, while stunting and anaemia were significantly associated with delayed AAG2.

CONCLUSION

Among adolescents living in the Karachi slum, stunting and highly prevalent anaemia delayed AAG2, while stunting, thinness and VAD delayed AAG2. Parental and household factors were not significantly associated with the timing of puberty onset.

Nasomaxillary and mandibular bone growth in primary school girls aged 7 to 12 years

Background/purpose

Facial bone growth manifests in primary school-aged children, especially girls. This study investigated the changes in nasomaxillary and mandibular morphology of primary school girls.

Materials and methods

Cephalograms of 60 primary school girls were divided into 3 groups (group I, aged 7–8 years; group II, aged 9–10 years; and group III, aged 11–12 years). The dimensions of the nasomaxilla (nasal bone length, nasal ridge length, nasal depth, palatal length, and maxillary height) and mandible (condylar length, condylar width, coronoid length, coronoid width, ramus length, body length, symphysis length, and entire mandibular length) were measured. One-way ANOVA and Pearson's correlation coefficient were used for statistical analysis.

Results

Nasal ridge length, nasal depth, and maxillary height were significantly greater in group III than in group I and group II. Condylar width and body length were significantly greater in group III than in group I and group II. Pearson's correlation revealed significant positive correlations between age and nasal ridge length, nasal depth, or maxillary height. There were also significant positive correlations between age and ramus length, body length, or entire length of the mandible.

Conclusion

We found that nasal ridge length, nasal depth, maxillary height, condylar width and body length were significantly greater in group III than in group I or in group II. Moreover, there were significant correlations between age and the nasal ridge length, nasal depth, maxillary height, ramus length, body length, or entire length of the mandible.

Association between pubertal development stages and body adiposity in children and adolescents

Background

The study aimed to analyze the association between pubertal development stages and adiposity in children and adolescents.

Methods

Cross-sectional study conducted in 2007 in Florianópolis, Brazil, with 2339 schoolchildren 32 aged 8 to 14 years old (1107 males). The outcome (adiposity) was evaluated using Z score and 33 percentilee values > = 85 of four skinfolds (triceps, subscapular, suprailiac and calf) and waist 34 circumference. Total body adiposity (Z score of the sum of skinfolds), central adiposity (Z score 35 of waist circumference) and peripheral adiposity (Z scores of triceps and calf skinfolds) were 36 estimated. Pubertal development stages was self-assessed according to Tanner stages of development. Thirty-seven Children and adolescents were classified according to tertiles of age for each pubertal development stages 38 stage - early, normal and late. Statistical analysis was performed using univariate and 39 multivariate Poisson regression models.

Results

Children and adolescent from both sexes with early pubertal development stages presented higher prevalence of central adiposity (waist circumference), with adjusted prevalence ratio (CI 95%) of 2.21 (1.12; 4.35) for males and 2.18 (1.04; 4.57) for females (reference group: normal pubertal development stages). Among females, there was a reduction in the prevalence of excess adiposity with decreased occurrence of early pubertal development stages. There was a strong relationship between adiposity and pubertal development stages.

Conclusions

Excess adiposity was higher in both sexes for those with early pubertal development stages.

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.

Nutritional Considerations for Sport Participation in Children and Adolescents With Obesity

There is a high prevalence of children with obesity who are participating in sports. Appropriate nutritional considerations are important to optimize health and training adaptations. This review focuses on macronutrient recommendations and their effect on weight management and/or benefits for athletic training for children ages 5 to 18 years. Equal distribution of protein intake throughout the day (~25-30 g/meal) and during postexercise recovery is recommended. Special attention should be given to increasing protein intake during breakfast because it is often the meal with the least protein intake. Both postexercise recommendations for protein (~0.3 g/kg of body weight) and carbohydrate (~1.0-1.2 g/kg/h) were not determined in children with obesity, and require future verification. Individual carbohydrate needs of training to meet fuel costs are recommended, but ~200 to 500 g/day of carbohydrate may be required depending on a child's level of sport participation and competition. Fat intake should follow general recommendations to meet the accepted macronutrient distribution range in children (25% to 35%) and reduce saturated fat intake. No evidence suggests that additional dietary fat modifications would improve training adaptations in children. Longitudinal studies are required to further our understanding of age and sex effects and confirm the appropriate quantity of macronutrients for active children with obesity.

Update on pubertal development in France. PROSPEL - Observational study. Preliminary feasibility study

INTRODUCTION

Recent publications report a decrease in the age of onset of pubertal changes in the United States and Europe. The PROSPEL study (PRemier Observatoire des Stades Pubertaire en Libéral) will provide the first French data on the age at which pubertal signs appear. Before considering this work at the national level, we wanted to assess its feasibility.

MATERIALS AND METHODS

Private pediatricians and general practitioners were recruited in Bordeaux and Toulouse. Before participating in the study, they had been trained in pubertal assessment and then evaluated. Each physician completed 1-4 weeks of inclusion during which children aged 5-18 years seen in consultation were included, except children who were adopted or had a chronic condition. Pubertal stages were assessed according to Tanner's classification and using an orchidometer for testicular volume. The causes of non-realization were documented where appropriate. Inter-individual reproducibility was analyzed by a double examination for a number of children who had previously given their consent.

RESULTS

In total, 63 physicians participated in the study (35 pediatricians and 28 general practitioners). All were certified at the end of the training session. A total of 2646 children were included (1318 girls, 1328 boys) with a homogeneous age distribution. The study was carried out in 83.5% of cases. The main reason for non-realization was that physicians did not propose the study to patients who met the criteria (10.1%). Lack of time was the main reason. Inter-individual reproducibility was excellent.

DISCUSSION AND CONCLUSION

Our results attest to the good feasibility of the PROSPEL study. They allowed us to validate our methodology, the training and certification of the participating physicians, and to consider extending the study to the national level.

Hypogonadism and Cryptorchidism

Congenital cryptorchidism (undescended testis) is one of the most common congenital urogenital malformations in boys. Prevalence of cryptorchidism at birth among boys born with normal birth weight ranges from 1.8 to 8.4%. Cryptorchidism is associated with a risk of low semen quality and an increased risk of testicular germ cell tumors. Testicular hormones, androgens and insulin-like peptide 3 (INSL3), have an essential role in the process of testicular descent from intra-abdominal position into the scrotum in fetal life. This explains the increased prevalence of cryptorchidism among boys with diseases or syndromes associated with congenitally decreased secretion or action of androgens, such as patients with congenital hypogonadism and partial androgen insensitivity syndrome. There is evidence to support that cryptorchidism is associated with decreased testicular hormone production later in life. It has been shown that cryptorchidism impairs long-term Sertoli cell function, but may also affect Leydig cells. Germ cell loss taking place in the cryptorchid testis is proportional to the duration of the condition, and therefore early orchiopexy to bring the testis into the scrotum is the standard treatment. However, the evidence for benefits of early orchiopexy for testicular endocrine function is controversial. The hormonal treatments using human chorionic gonadotropin (hCG) or gonadotropin-releasing hormone (GnRH) to induce testicular descent have low success rates, and therefore they are not recommended by the current guidelines for management of cryptorchidism. However, more research is needed to assess the effects of hormonal treatments during infancy on future male reproductive health.

Noonan syndrome males display Sertoli cell-specific primary testicular insufficiency

Context Abnormalities in the hypothalamo-pituitary-gonadal axis have long been reported in Noonan syndrome (NS) males with only few data available in prepubertal children. Objective The aim of this study was to describe the gonadal function of NS males from childhood to adulthood. Design It is a retrospective chart review. Patients and methods A total of 37 males with a genetically confirmed diagnosis of NS were included. Clinical and genetic features, as well as serum hormone levels (LH, FSH, testosterone, anti-Müllerian hormone (AMH), and inhibin B) were analysed. Results Of the 37 patients, 16 (43%) children had entered puberty at a median age of 13.5 years (range: 11.4-15.0 years); age at pubertal onset was negatively correlated with BMI SDS (r = -0.541; P = 0.022). In pubertal boys, testosterone levels were normal suggesting a normal Leydig cell function. In contrast, NS patients had significant lower levels of AMH (mean SDS: -0.6 ± 1.1; P = 0.003) and inhibin B (mean SDS: -1.1 ± 1.2; P < 0.001) compared with the general population, suggesting a Sertoli cell dysfunction. Lower AMH and inhibin B levels were found in NS-PTPN11 patients, whereas these markers did not differ from healthy children in SOS1 patients. No difference was found between cryptorchid and non-cryptorchid patients for AMH and inhibin B levels (P = 0.43 and 0.62 respectively). Four NS-PTPN11 patients had a severe primary hypogonadism with azoospermia/cryptozoospermia. Conclusions NS males display Sertoli cell-specific primary testicular insufficiency, whereas Leydig cell function seems to be unaffected.

Association of prepubertal obesity with pubertal development in Chinese girls and boys: A longitudinal study

OBJECTIVES

The purpose of this study was to examine the association of prepubertal body mass index (BMI) and weight status with pubertal development in boys and girls in Chongqing, China.

METHODS

In a longitudinal study, 1237 students (695 boys and 542 girls) were recruited from Chongqing, China, and examined at baseline, then followed every 6 months for three and a half years. Height, weight, testicular volume, and breast development were measured at every examination. Age of first spermatorrhea and menarche were obtained from self-report. Subjects were divided into normal weight, overweight, and obese groups according to baseline BMI. Multivariable Cox regression analysis was used to examine the association of BMI and weight status with pubertal development.

RESULTS

In girls, higher prepubertal BMI increased the chance of earlier menarche (hazards ratio (HR): 1.205, 95% confidence interval (95% CI): 1.151-2.261) and breast development (HR: 1.092, 95% CI: 1.045-1.142). Girls in the overweight (HR: 2.605, 95% CI: 1.716-3.956) and obese (HR: 2.565, 95% CI: 1.603-4.103) groups had an increased risk of early menarche compared with those in the normal weight group, while only overweight was associated with an increased risk for earlier breast development (HR: 1.469, 95% CI: 1.024-2.108). In boys, higher prepubertal BMI was significantly associated with the timing of first spermatorrhea (HR: 1.054, 95% CI: 1.004-1.106) and testicular development (HR: 1.098, 95% CI: 1.063-1.135). Overweight (HR: 1.672, 95% CI: 1.204-2.322) and obesity (HR: 1.598, 95% CI: 1.135-2.249) increased the hazard of earlier testicular development compared with the normal weight group, while no significant differences were detected among the three weight groups in terms of time to first spermatorrhea.

CONCLUSIONS

Higher prepubertal BMI was associated with earlier puberty in both Chinese boys and girls.

Girls and Boys Have a Different Cardiometabolic Response to Obesity Treatment

Background: Childhood obesity exposes individuals to cardiometabolic disturbances. We analyzed how family-based multidisciplinary obesity treatment influenced children's cardiometabolic health. Materials and methods: In this retrospective, two-year, follow-up study of 654 2- to 18-year-old children treated for obesity in three Finnish pediatric clinics in 2005-2012, blood pressure (BP), metabolic parameters, and the influence of sex, puberty and a change in body mass index standard deviation score (BMI SDS) were analyzed. Results: At baseline, at least one cardiovascular risk factor was present in 474 (80%) cases. Boys presented with more significant changes in cardiometabolic parameters than girls during the treatment. Boys' total cholesterol (TC) improved by 12 months (P = 0.009), and their low-density lipoprotein C (LDL-C) and glycosylated hemoglobin ameliorated by 12 months (P = 0.030 and 0.022, respectively) and 24 months (P = 0.043 and 0.025, respectively). Boys' triglycerides, insulin, homeostasis model assessment for insulin resistance (HOMA-IR) and systolic BP deteriorated at 24 months (P < 0.001, 0.004, 0.002, and 0.037, respectively). In all children, the number of acceptable TC, LDL-C, insulin, and HOMA-IR values increased if BMI SDS reduced 0.25 or more by 12 months. Conclusion: Minor cardiometabolic improvements were found during the obesity treatment. These findings indicate the need to assess treatment methods and focus on prevention.

Paediatric obesity treatment had better outcomes when children were younger, well motivated and did not have acanthosis nigricans

AIM

This study evaluated the efficacy of a paediatric obesity treatment programme and explored the factors that contributed to the outcome.

METHODS

We recorded the body mass index standard deviation scores (BMI SDS) of 654 children aged 2-18 years who were treated for obesity in 2005-2012 in three Finnish hospitals, one year before treatment and up to three years after treatment. The family-based multidisciplinary treatment included nutritional advice, exercise and behavioural counselling. The BMI SDS changes, and their contributors, were explored with mixed-model and logistic regression analyses.

RESULTS

BMI SDS increased before baseline and decreased at six, 12 and 24 months (all p < 0.001) and 36 months (p = 0.005). Younger age (p < 0.001), higher BMI SDS at baseline (p = 0.001), motivation (p = 0.013), adherence to the protocol (p = 0.033) and lack of acanthosis nigricans (p < 0.001) improved the outcome. The BMI SDS of children aged 2-6 decreased best from baseline to 12 (-0.35), 24 (-0.58) and 36 months (-0.64) (all p < 0.001).

CONCLUSION

Paediatric obesity treatment was most effective at a younger age. Good motivation and adherence contributed to favourable outcomes, while acanthosis nigricans was associated with a poor outcome.

Race disparities in pubertal timing: Implications for cardiovascular disease risk among African American women

Compared to white girls, sexual maturation is accelerated in African American girls as measured by indicators of pubertal development, including age at first menses. Increasing epidemiological evidence suggests that the timing of pubertal development may have strong implications for cardio-metabolic health in adolescence and adulthood. In fact, younger menarcheal age has been related prospectively to poorer cardiovascular risk factor profiles, a worsening of these profiles over time, and an increase in risk for cardiovascular events, including non-fatal incident cardiovascular disease and cardiovascular-specific and all-cause mortality. Yet, because this literature has been limited almost exclusively to white girls/women, whether this same association is present among African American girls/women has not been clarified. In the current narrative review, the well-established vulnerability of African American girls to experience earlier pubertal onset is discussed as are findings from literatures examining the health outcomes of earlier pubertal timing and its antecedents, including early life adversity exposures often experienced disproportionately in African American girls. Gaps in these literatures are highlighted especially with respect to the paucity of research among minority girls/women, and a conceptual framework is posited suggesting disparities in pubertal timing between African American and white girls may partially contribute to well-established disparities in adulthood risk for cardio-metabolic disease between African American and white women. Future research in these areas may point to novel areas for intervention in preventing or lessening the heightened cardio-metabolic risk among African American women, an important public health objective.

Testicular growth and development in puberty

PURPOSE OF REVIEW

To describe pubertal testicular growth in humans, changes in testicular cell populations that result in testicular growth, and the role of testosterone and gonadotrophins follicle-stimulating hormone (FSH) and luteinizing hormone (LH) in testicular growth. When human data were not available, studies in nonhuman primates and/or rodents were used as surrogates.

RECENT FINDINGS

Testicular growth in puberty follows a sigmoidal growth curve, with a large variation in timing of testicular growth and adult testicular volume. Testicular growth early in puberty is due to increase in Sertoli cell number and length of seminiferous tubules, whereas the largest and fastest growth results from the increase in the diameter of the seminiferous tubules first due to spermatogonial proliferation and then due to the expansion of meiotic and haploid germ cells. FSH stimulates Sertoli cell and spermatogonial proliferation, whereas LH/testosterone is mandatory to complete spermatogenesis. However, FSH and LH/testosterone work in synergy and are both needed for normal spermatogenesis.

SUMMARY

Testicular growth during puberty is rapid, and mostly due to germ cell expansion and growth in seminiferous tubule diameter triggered by androgens. Pre-treatment with FSH before the induction of puberty may improve the treatment of hypogonadotropic hypogonadism, but remains to be proven.

Pubertal Onset in Apparently Healthy Indian Boys and Impact of Obesity

OBJECTIVE

Primary - to determine the age of pubertal onset in Indian boys. Secondary - (a) to assess the impact of obesity on pubertal timing, (b) to assess the relationship between gonadotropins and puberty.

DESIGN

Cross-sectional.

SETTING

General community-seven schools across New Delhi.

PARTICIPANTS

Random sample of 1306 school boys, aged 6-17 years.

MATERIALS AND METHODS

Anthropometric measurement for weight and height and pubertal staging was performed for all subjects. Body mass index (BMI) was calculated to define overweight/obesity. Serum luteinizing hormone (LH), follicle stimulating hormone, and serum testosterone were measured in every sixth subject.

MAIN OUTCOME MEASURE

Age at pubertal onset-testicular volume ≥4 mL (gonadarche) and pubic hair Stage II.

RESULTS

Median age of attaining gonadarche and pubarche was 10.41 years (95% confidence interval [CI]: 10.2-10.6 years) and 13.60 (95% CI: 13.3-14.0 years), respectively. No significant difference in the age of attainment of gonadarche was observed in boys with normal or raised BMI, though pubarche occurred 8 months earlier in the latter group. Serum gonadotropins and testosterone increased with increasing stages of puberty but were unaffected by BMI. Serum LH level of 1.02 mIU/mL and testosterone level of >0.14 ng/mL showed the best prediction for pubertal onset.

CONCLUSION

The study establishes a secular trend of the age of onset of puberty in Indian boys. Pubarche occurred earlier in overweight/obese boys. The cutoff levels of serum LH and testosterone for prediction of pubertal onset have been established.

Pubertal height gain is inversely related to peak BMI in childhood

BACKGROUND

Childhood BMI may influence subsequent growth in height as well as the timing of puberty. The aim of the present study was to investigate associations between BMI in childhood and subsequent height gain/pubertal growth.

METHODS

Longitudinal growth data were used (GrowUp₁₉₉₀Gothenburg cohort, n = 1,901). The QEPS growth-model was used to characterize height gain in relation to the highest BMI_SDS value between 3.5 and 8 y of age. Children were defined as overweight/obese (OwOb) or normal weight/underweight (NwUw), using the 2012 International Obesity Task Force criteria.

RESULTS

A negative association between childhood BMI_SDS and pubertal height gain was observed. Already at birth, OwOb children were heavier than NwUw children, and had a greater height velocity during childhood. Onset of puberty was 3.5/3.0 mo earlier in OwOb girls/boys, and they had 2.3/3.1 cm less pubertal height gain from the QEPS-models specific P-function than NwUw children. Adult height was not related to childhood BMI.

CONCLUSION

We found that pubertal height gain was inversely related to peak BMI in childhood. Higher childhood BMI_SDS was associated with more growth before onset of puberty, earlier puberty, and less pubertal height gain, resulting in similar adult heights for OwOb and NwUw children.

Could tea polyphenols be beneficial for preventing the precocious puberty?

Precocious puberty which impacts children physically and psychologically has become one of the health problem over the world. However, the mechanism and preventive measures of precocious puberty is still not clear. Recent studies suggested that leptin may act as the 'permissive factor' to initiate the puberty by regulating gonadotrophin-releasing hormone secretion. Previous evidence from animal and human studies found that tea polyphenols can reduce serum leptin levels in vivo and inhibit the expression of leptin in adipose tissue. This article focus on whether tea polyphenols could delay the onset of puberty by reducing leptin levels. To verify the possibility of tea polyphenols on preventing precocious puberty, animal experiment can be used. Our hypothesis that tea polyphenols could prevent the precocious puberty may provide important potential way for the prevention and control of children precocious puberty.

Age at spermarche: 15-year trend and its association with body mass index in Chinese school-aged boys

BACKGROUND

Little is known about the secular trends in age at spermarche among boys, and the association between body mass index (BMI) and male puberty is controversial.

OBJECTIVE

This study aimed to estimate the trend in age at spermarche in China and explore the association of spermarche with BMI.

METHODS

We used four cross-sectional Chinese National Surveys on Students' Constitution and Health (CNSSCH; 1995, 2000, 2005 and 2010). Median age at spermarche was determined using probit analysis. Logistic regression was used to assess the association of spermarche with BMI.

RESULTS

Age at spermarche among Chinese boys dropped from 14.57 to 14.03 years from 1995 to 2010 with a decrease of 4.3 months per decade. Boys with BMI-for-age z-score lower than -2 had the latest age at spermarche. A higher BMI or BMI-for-age z-score was associated with an increased likelihood of having reached spermarche, and this association was consistently observed at all survey points.

CONCLUSION

This study provides important evidence of a secular trend of earlier age at spermarche over the past 15 years in China, and this decrease was accompanied by a simultaneous increase in BMI. Strategies and interventions focusing on thinness may promote both their nutritional status and puberty development among Chinese boys.

Infection and pubertal timing: a systematic review

The decline in age of pubertal timing has serious public health implications ranging from psychosocial adjustment problems to a possible increase in reproductive cancers. One biologically plausible explanation for the decline is a decrease in exposures to infections. To systematically review studies that assess the role of infection in pubertal timing, Medline, Web of Science and EMBASE were systematically searched and retrieved studies were reviewed for eligibility. Eligible studies examined the association between infections, including microbial exposures, and physical pubertal characteristics (breast, genitalia and pubic hair development) or age at menarche. We excluded studies that were published in a language other than English, focused on precocious puberty, were case studies, and/or included youth with autoimmune diseases. We report on study design, population characteristics, measurement of infection and puberty and the main effects of infection on pubertal development. Based on our search terms we identified 1372 unique articles, of which only 15 human and five animal studies met our eligibility criteria. Not all studies examined all outcomes. Infection was associated with later breast development (4/4 human studies), with less consistent evidence for genitalia and pubic hair development. Seven studies assessed age at menarche with inconsistent findings (three supporting later, four no association). We conclude that a small but consistent literature supports that infection is associated with later breast development; the evidence for other pubertal events and age at menarche is less clear. Where fewer childhood infections coincide with the rise in incidence of hormone-related cancers.

Early Life Growth Predicts Pubertal Development in South African Adolescents

BACKGROUND

Given global trends toward earlier onset of puberty and the adverse psychosocial consequences of early puberty, it is important to understand the childhood predictors of pubertal timing and tempo.

OBJECTIVE

We examined the association between early growth and the timing and tempo of puberty in adolescents in South Africa.

METHODS

We analyzed prospectively collected data from 1060 boys and 1135 girls participating in the Birth-to-Twenty cohort in Soweto, South Africa. Height-for-age z scores (HAZs) and body mass index-for-age z scores (BMIZs) were calculated based on height (centimeters) and body mass index (kilograms per meter squared) at ages 5 y and 8 y. The development of genitals, breasts, and pubic hair was recorded annually from 9 to 16 y of age with the use of the Tanner sexual maturation scale (SMS). We used latent class growth analysis to identify pubertal trajectory classes and also characterized children as fast or slow developers based on the SMS score at 12 y of age. We used multinomial logistic regression to estimate associations of HAZ and BMIZ at ages 5 and 8 y with pubertal development.

RESULTS

We identified 3 classes for pubic hair development (for both girls and boys) and 4 classes for breast (for girls) and genital (for boys) development. In girls, both HAZ and BMIZ at age 5 y were positively associated with pubic hair development [relative risk ratio (RRR): 1.57, P < 0.001 and RRR: 1.51, P < 0.01, respectively], as was BMI at age 8 y (RRR: 2.06, P = 0.03); similar findings were observed for breast development. In boys, HAZ and BMIZ at age 5 y were positively associated with pubic hair development (RRR: 1.78, P < 0.001 and RRR: 1.43, P < 0.01, respectively); HAZ at age 5 y was associated with development of genitals (RRR: 2.19, P < 0.01).

CONCLUSION

In boys and girls, both height and body mass index in early childhood predicted the trajectory of pubertal development. This may provide a tool to identify children at risk of early pubertal onset.

The Health Consequences of Obesity in Young Adulthood

Young adults are gaining weight faster than any age group. This weight gain and the appearance of obesity-related comorbidities often commence in adolescence. Psychosocial distress and mental health issues are common and debilitating, and treatment approaches are likely to be similar to those for adolescents. At the same time, young adults may have physical morbidities which will continue and worsen throughout adulthood, such as hypertension, diabetes and polycystic ovarian syndrome. Health consequences of obesity are challenging to manage in young adults as their symptoms may be minimal, they are less likely to engage with healthcare due to other life priorities and their neurocognitive developmental stage makes therapy adherence difficult. Clinicians who manage young adults with obesity need to be aware of these age-specific challenges, as well as the sexual and reproductive health concerns that are present in this age group.

Secular trends for age at spermarche among Chinese boys from 11 ethnic minorities, 1995-2010: a multiple cross-sectional study

OBJECTIVES

We compared the differences in median age at spermarche among 11 ethnic minorities in 2010, estimated the trends regarding age at spermarche in different ethnic minorities from 1995 to 2010, and explored the association of spermarche with body mass index (BMI).

METHODS

We used four cross-sectional Chinese National Surveys on Students' Constitution and Health (CNSSCH, 1995, 2000, 2005 and 2010), and the total sample size was 40,113 children aged 11-18 years. The median age at spermarche of each ethnic minority was determined by using probit analysis. Logistic regression was used to assess the association of spermarche with BMI.

RESULTS

In 2010, the ethnic minorities with earliest age at spermarche were Qiang (12.03 years), Zhuang (12.91 years) and Kirghiz (13.17 years); the three ethnic minorities with latest age at spermarche were Dong (14.73 years), Yao (14.60 years), and Naxi (14.36 years). From 1995 to 2010, age at spermarche showed a decline in almost each minority group except Yao and Dong. A higher BMI was associated with an increased likelihood of having reached spermarche after adjusting for age, regions or ethnic minorities.

CONCLUSIONS

A large variation in age at spermarche was observed among different ethnic minorities. The age at spermarche showed a downward shift in almost each of the 11 ethnic minorities with different patterns over time, and the children with higher BMI are more likely to enter puberty early.

Nutritional Determinants of the Timing of Puberty

The timing of puberty has important public health, clinical, and social implications. The plasticity of sexual development onset could be a mechanism that adapts to prevailing environmental conditions. Early-life nutrition may provide cues for the environment's suitability for reproduction. This review focuses on recent developments in our understanding of the role of diet in the timing of sexual maturation. Population-based observational studies consistently indicate that childhood obesity is related to the earlier onset of puberty in girls. Similarly, intake of animal foods has been associated with earlier sexual development, whereas vegetable protein intake is related to delayed maturation. Evidence for prenatal nutrition, infant feeding practices, and childhood intake of fat, carbohydrate, and micronutrients is inconsistent. Secondary analyses of prenatal and early-life randomized nutritional interventions with extended follow-up through peripubertal years would help clarify the role of nutrition in the timing of sexual maturation.

Spermatogenesis in Hodgkin's lymphoma patients: a retrospective study of semen quality before and after different chemotherapy regimens

STUDY QUESTION

Is spermatogenesis impairment caused by Hodgkin's lymphoma (HL) itself or by the various treatments?

SUMMARY ANSWER

HL is not itself the main cause of impaired spermatogenesis, which is instead affected by the treatment; the extent of impairment depends on the type of treatment and the number of cycles.

WHAT IS KNOWN ALREADY

Data in the literature are contradictory, although most studies found poor semen quality in HL patients prior to treatment. The impact of therapy on spermatogenesis depends on the type of treatment, but the time needed to recover testicular function following treatment with chemotherapeutic agents inducing azoospermia is unknown.

STUDY DESIGN, SIZE, DURATION

In a retrospective study, the semen parameters of 519 patients (504 with sperm and 15 who were azoospermic) were investigated.HL patients were analysed before therapy. A longitudinal study was also conducted of semen quality in 202 patients pre- and post-ABVD (doxorubicin, bleomycin, vinblastine and dacarbazine) at T0 (baseline) and 6 (T6), 12 (T12) and 24 (T24) months after the end of treatment, and of 42 patients pre- and post-BEACOPP (bleomycin, etoposide, doxorubicin, cyclophosphamide, vincristine, procarbazine, prednisone), COPP/ABVD (cyclophosphamide, vincristine, procarbazine, prednisone, doxorubicin, bleomycin, vinblastine and dacarbazine), OPP/ABVD (vincristine, procarbazine, prednisone, doxorubicin, bleomycin, vinblastine and dacarbazine) or MOPP (mechlorethamine, vincristine, procarbazine and prednisone) and inguinal radiotherapy at different observation times (from T0 to 16 years after treatment).

PARTICIPANTS/MATERIALS, SETTING, METHODS

Semen parameters were examined according to World Health Organization 2010 criteria, evaluating sperm concentration, total sperm number, progressive motility and morphology.

MAIN RESULTS AND THE ROLE OF CHANCE

Our data, which pertain to the largest caseload reported to date, indicate that 75% of HL patients are normozoospermic prior to treatment. The results from the HL patients studied pre- and post-therapy demonstrate that spermatogenesis recovery depends on the therapeutic regimen used. After ABVD, there was a statistically significant decrease in sperm concentration and total sperm number at T6 and T12 (P < 0.001; P < 0.01, respectively). There was a significant drop in progressive motility (P < 0.001) and a significant increase in abnormal forms (P < 0.01) at T6. The differences in sperm concentration, total sperm number and abnormal forms at T0 and T24 were not statistically significant, indicating that sperm quality had returned to pre-therapy values. The most interesting data in terms of patient management arise from the study of azoospermia induced by other chemotherapeutic agents. A high number of BEACOPP, COPP/ABVD, OPP/ABVD or MOPP cycles (≥6) induced a permanent absence of sperm in the seminal fluid, while even following a low number of cycles (<6), spermatogenesis only recovered after 3-5 years and semen quality was highly impaired.

LIMITATIONS, REASONS FOR CAUTION

The study type (retrospective) and the low caseload and varying time of the follow-up do not permit any firm conclusions to be drawn about the recovery of spermatogenesis after BEACOPP or other combined therapies, or the identification of any risk factors for testicular function in treated patients.

WIDER IMPLICATIONS OF THE FINDINGS

The pretreatment semen parameters of HL patients in this study were better than some results reported in the literature, with a higher percentage of normozoospermic patients. Strengths of this study were the large caseload of HL patients and a high degree of consistency in semen analysis, as all parameters were assessed in the same laboratory. Following the azoospermia induced by different chemotherapeutic protocols, spermatogenesis may take several years to recover. Awareness of this issue will enable oncologists to better inform patients about the possibility of recovering fertility post-treatment and also demonstrates the importance of semen cryobanking before beginning any cancer treatment.

STUDY FUNDING/COMPETING INTERESTS

Supported by a grant from the Italian Ministry of Education and Research (MIUR-PRIN) and the University of Rome 'La Sapienza' Faculty of Medicine. The authors have no conflicts of interest.

Does salt have a permissive role in the induction of puberty?

Puberty is starting earlier than ever before and there are serious physiological and sociological implications as a result of this development. Current research has focused on the potential role of high caloric, and commensurate high adiposity, contributions to early puberty. However, girls with normal BMI also appear to be initiating puberty earlier. Westernized diets, in addition to being high in fat and sugar, are also high in salt. To date, no research has investigated a link between elevated salt and the reproductive axis. We hypothesize that a high salt diet can result in an earlier onset of puberty through three mechanisms that are not mutually exclusive. (1) High salt activates neurokinin B, a hormone that is involved in both the reproductive axis and salt regulation, and this induces kisspeptin release and ultimate activation of the reproductive axis. (2) Vasopressin released in response to high salt acts on vasopressin receptors expressed on kisspeptin neurons in the anteroventral periventricular nucleus, thereby stimulating gonadotropin releasing hormone and subsequently luteinizing hormone secretion. (3) Salt induces metabolic changes that affect the reproductive axis. Specifically, salt acts indirectly to modulate adiposity, ties in with the obesity epidemic, and further compounds the pathologic effects of obesity. Our overall hypothesis offers an additional cause behind the induction of puberty and provides testable postulates to determine the mechanism of potential salt-mediated affects on puberty.

Childhood obesity in specialist care--searching for a healthy obese child

INTRODUCTION

One in three obese adults is classified as metabolically healthy, but there is less evidence in obese children. We studied the overall clinical presentation of Finnish obese children and the prevalence of cardiometabolic risk factors with child-specific cut-offs.

MATERIAL AND METHODS

This is a cross-sectional register-based study of 2-18-year-old children (n = 900) evaluated for obesity in three hospitals in 2005-2012. Clinical and metabolic data were related to sex, age, puberty, and obesity grade and analyzed using chi-square and non-parametric tests.

RESULTS

In 80% of cases at least one cardiovascular risk factor was present. Only 3% of subjects for whom complete metabolic data were available (n = 360) had no metabolic disorder. Systolic blood pressure was hypertensive in 50.2% and diastolic in 14.5% of the children. The youngest children had highest body mass index SD score. Obesity was more severe in boys than girls (p < 0.001). Hypertensive systolic blood pressure values (p = 0.012), prediabetes (p < 0.001), fatty liver (p < 0.001), and dyslipidemia (p = 0.025) were more prevalent in 15-18-year-old boys than girls.

CONCLUSION

Most obese children in specialist care have cardiovascular risk factors; this indicates that earlier intervention is needed.

[Contribution of anthropometric characteristics to pubertal stage prediction in young male individuals]

OBJECTIVE

To identify the contribution of anthropometric variables to predict the maturational stage in young males.

METHODS

Cross-sectional study that enrolled 190 male subjects aged between eight and 18 years, randomly selected from public and private schools in Natal, Northeast Brazil. Thirty-two anthropometric variables were measured following the recommendations of the International Society for the Advancement of Kineanthropometry (ISAK). The assessment of sexual maturation was based on the observation of two experienced experts, who identified the pubertal development according to Tanner guidelines (1962).

RESULTS

The anthropometric variables showed a significant increase of their values during the advancement of pubertal development (p<0.05). The following variables showed the best value for prediction of maturational groups: sitting height, femoral biepicondylar diameter, forearm girth, triceps skinfold, tibiale laterale and acromiale-radiale bone lenghts. These variables were able to estimate the pubertal stages in 76.3% of the sujects.

CONCLUSION

The anthropometric characteristics showed significant differences between the moments of maturational stages, being found, representatively, seven variables that best predict the stages of sexual maturation.

The gonadal function in obese adolescents: review

This review deals with the relationship between obesity in male adolescents and gonadal function. The article is structured in two main paragraphs; the first one is about population studies that have assessed puberty timing and its mode of onset in relation with body weight to evaluate if and how the latter can influence the gonadal function in this phase of life. These studies analyze issues such as increased BMI and early onset of male puberty, gender differences, secular trend toward early onset of puberty in males, effects of a different body composition on male puberty and consequences of a different stage of childhood obesity on the onset of male puberty. The second paragraph examines the possible mechanisms through which, obesity may alter the timing of puberty in young males, including the role of SHBG, leptin, insulin resistance, ghrelin, GH-IGF-1 axis, AR polymorphisms, primary testicular dysfunction, retinol binding protein 4 (RBP-4) and liver function abnormalities. However, despite the numerous studies in the literature, the etiology of gonadal disfunction in obese adolescents on puberty remains uncertain.

Age at hormonal onset of puberty based on luteinizing hormone, inhibin B, and body composition in preadolescent U.S. girls

BACKGROUND

Hormonal indicators could be useful for detecting early pubertal onset, but there is little research on how they are related to puberty in U.S. girls. We determined median age at hormonal onset of puberty based on luteinizing hormone (LH) and inhibin B (InB) and explored the extent to which body composition moderates this timing process.

METHODS

We analyzed anthropometric and hormone data of 698 US peri-pubertal girls ages 6-11.99 y who had participated in the Third National Health and Nutrition Examination Survey (NHANES III), 1988-1994.

RESULTS

Median age of hormonal onset of puberty was 10.43 y by LH and 10.08 y by InB cut-offs (1.04 mIU/ml for LH and 17.89 pg/ml for InB). Postnatal weight gain modulated onset, making it earlier by 10-11 mo among the highest (greater than +1 SD) relative to normal weight gainers. Onset occurred first in non-Hispanic black (NHB) girls, 10.08 y (95% confidence interval (CI): 10.07-10.09), followed by Mexican-American (MXAM) at 10.64 y (95% CI: 10.63-10.65), and at 10.66 y (95% CI: 10.66-10.67) for non-Hispanic white (NHW) girls using LH. With InB, onset occurred first in MXAM girls at 9.9 y, and at 10.3 y and 10.4 y for their NHB and NHW peers, respectively.

CONCLUSION

Preadolescent weight gain lowers the age at hormonal onset as defined by LH concentrations. Preventing obesity in childhood may also avert the earlier initiation of the maturation process even at the hormonal level.

Nutrition and pubertal development

Nutrition is one of the most important factors affecting pubertal development. Puberty entails a progressive nonlinear process starting from prepubescent to full sexual maturity through the interaction and cooperation of biological, physical, and psychological changes. Consuming an adequate and balanced healthy diet during all phases of growth (infancy, childhood and puberty) appears necessary both for proper growth and normal pubertal development. Girls begin puberty at an earlier age compared to past decades. Excessive eating of many processed, high-fat foods, may be the cause of this phenomenon. Overweight or obese children are more likely to enter puberty early. Some evidence suggests that obesity can accelerate the onset of puberty in girls and may delay the onset of puberty in boys. Moreover, the progression of puberty is affected by nutrition. On the other hand, puberty triggers a growth spurt, which increases nutritional needs including macro and micronutrients. Increased caloric, protein, iron, calcium, zinc and folate needs have to be provided during this critical period of rapid growth. Severe primary or secondary malnutrition also can delay the onset and progression of puberty. The higher incidence of anorexia nervosa and bulimia in adolescents imposes a nutritional risk on pubertal development. Moreover, many environmental endocrine disruptors (EDs) have been identified that can significantly impair the normal course of puberty. This mini-review sums up some important findings in this important complex that link nutrition and pubertal development.

Timing of puberty and physical growth in obese children: a longitudinal study in boys and girls

OBJECTIVE

To assess whether puberty and physical growth vary in obese when compared to normal-weight children.

METHODS

One hundred obese pre-pubertal children (44 boys; mean age (±SD): 9.01 ± 0.62 years; 56 girls; 8.70 ± 0.57 years) were compared to 55 normal-weight controls (27 boys; 9.17 ± 0.26 years; 28 girls; 8.71 ± 0.62 years). All study participants were followed prospectively with 6-monthly follow-up visits. At each study visit, height, weight, body mass index (BMI) and pubertal stage were assessed.

RESULTS

Obese children entered puberty and achieved later stages of puberty earlier than controls (onset of puberty: boys: 11.66 ± 1.00 vs. 12.12 ± 0.91 years, P = 0.049; girls: 9.90 ± 0.78 vs. 10.32 ± 1.70, P = 0.016; late puberty: boys: 13.33 ± 0.71 vs. 14.47 ± 1.00 years, P < 0.001; girls: 11.54 ± 0.99 vs. 12.40 ± 1.02, P = 0.001). Pre-pubertal BMI standard deviation score (SDS) was inversely associated with both age at the onset of puberty (β = -0.506, P < 0.001) and age at late puberty (β = -0.514, P < 0.001). Obese children also showed an earlier age at peak height velocity (PHV) (boys: 12.62 ± 0.82 vs. 13.19 ± 0.96 years, P = 0.01; girls: 11.37 ± 0.89 vs. 12.77 ± 0.76, P < 0.001) and a lower PHV (boys: 7.74 ± 1.49 vs. 9.28 ± 1.64 cm year(-1) , P < 0.001; girls: 7.60 ± 1.64 vs. 8.29 ± 1.03, P = 0.03). Height SDS progressively declined over the study period in the obese group (P for trend <0.001), whereas there were no significant changes in the control group (P for trend = 0.5).

CONCLUSIONS

Obese boys and girls presented an earlier onset of puberty and completion of puberty and an impaired height gain during puberty.