Worldwide Secular Trends in Age at Pubertal Onset Assessed by Breast Development Among Girls: A Systematic Review and Meta-analysis

Precocious Puberty Diagnoses Spike, COVID-19 Pandemic, and Body Mass Index: Findings From a 4-year Study

Context

Since the COVID-19 outbreak, the number of girls with suspected precocious puberty has increased.

Objective

To compare the incidence of idiopathic central precocious puberty (ICPP) during COVID-19 with that of the previous 4 years.

Methods

Anthropometric, biochemical, and radiological parameters were collected between January 2016 and June 2021 from 133 girls who met the Rapidly Progressive ICPP criteria (RP-ICPP).

Results

We found a higher incidence of RP-ICPP between March 2020 and June 2021 (group 2) compared with January 2016 through March 2020 (group 1) (53.5% vs 41.1%); 2021 showed the highest annual incidence (P < .05). Group 1 and group 2 differed in age at diagnosis (7.96 ± 0.71 vs 7.61 ± 0.94; P < .05), mean Tanner stage (2.86 ± 0.51 vs 2.64 ± 0; P < .05), and in the time between the appearance of thelarche and diagnosis (0.93 ± 0.75 vs 0.71 ± 0.62 years, P < .05). There was an increase in the number of girls aged <8 years in group 2 and a significantly higher number of girls aged >8 years was found in group 1 (42 in group 1 vs 20 in group 2, P < 0.05). Overall body mass index SD score showed higher values ​​in group 2 (1.01 ± 1.23 vs 0.69 ± 1.15; P = .18), which spent an average of 1.94 ± 1.81 hours per day using electronic devices; 88.5% of this group stopped any physical activity.

Conclusions

A spike in new diagnoses of idiopathic (1.79-fold higher) and RP-CPP coincided with the COVID-19 pandemic. The incidence of RP-ICPP was 1.3-fold higher during COVID-19 with a trend toward an increase in body mass index SD score. The expanding use of digital devices and the reduction of daily physical activity represent possible risk factors.

Association between dental and skeletal maturation in Scandinavian children born between 2005 and 2010

OBJECTIVE

The aim of this cross-sectional study was to analyse the association between dental and skeletal maturation in children born between 2005 and 2010.

MATERIALS AND METHODS

Dental and skeletal maturation of 117 ethnic Scandinavian children born between 2005 and 2010 (70 girls, 47 boys, mean age 11.48 years) was analysed. Dental maturation (DM) was assessed on orthopantomographs (OPs) by using Demirjian's and Haavikko's methods while skeletal maturation was assessed on hand-wrist radiographs by use of Helm's method. The correlation between skeletal and DM was analysed using Spearman's rho (Rs). Additionally, the most frequent DM stage in relation to the skeletal maturation stage was analysed by logistic regression adjusted for age and sex.

RESULTS

The correlation between dental and skeletal maturation was significant for all teeth (Rs = 0.071-0.562; p < .000-p = .035) except for the first incisor and the first molar. Logistic regression analysis showed that when the mandibular and maxillary canines are ¾ mineralized, this is significantly associated with the beginning of the adolescent period before peak height velocity (PHV) (PP2= p < .005-< .05). Likewise, when the mandibular second premolars are ¾ mineralized, this is significantly associated with the maturation stage PP2= or S (PP2= p < .05, S: p < .005-< .05), both of which are before PHV at the beginning of the adolescent period.

LIMITATIONS

Limited sample size and the X-rays were taken before orthodontic treatment, which may have introduced a selection bias.

CONCLUSIONS

When the root of the canines or second premolars is ¾ mineralized, it may indicate the beginning of the adolescent period with increased skeletal growth intensity.

Knowledge, Beliefs, and Practices Related to Menstruation Among Female Students in Afghanistan

Background

Menstruation is a universal, natural, unique, and physiological phenomenon. Despite the fact that menstruation is a natural fact of life, it is still considered taboo in Afghanistan and other developing countries.

Objective

To assess knowledge, beliefs, and practices related to menstruation among female students of Kabul University of Medical Sciences (KUMS).

Methods

A cross-sectional descriptive study design was conducted at KUMS in 2022, and a quota sampling technique was used.

Results

In this study, 339 students participated out of the 346-sample size. The majority of participants (70.02%), were over 20 years of age. About (59.60%) of participants were aware of menstruation before menarche. The main source of their information was their mothers (37.50%). The average age of menarche was 13.5 years old. Above 70% of respondents had normal patterns of menstruation. More than half of them (51.90%) had dysmenorrhea. Frequent menstrual disorders were abdominal pain (58.1%), and backache (56.1%). The majority of respondents had good and acceptable knowledge of menstruation (33.6%), and (63.1%) respectively. A statistically significant relationship between knowledge and academic year was observed (P value = 0.005). The majority of respondents (92.6%) had poor menstrual beliefs. A statistically significant relationship between respondents' age and beliefs was observed (P value = 0.004). Mother education did not affect respondents' level of beliefs (P value = 0.4). In addition, respondents had good practice of menstruation (75%).

Conclusion

In general participants had a good and acceptable level of knowledge with good practice related to menstruation. Despite the good knowledge and practice, the respondents' beliefs related to menstruation were poorer than what was expected from medical disciplines students. Their frequent source of information was their mothers, which highlights the provision of information and education for mothers and all females.

Rapid weight gain in early life is associated with central precocious puberty in girls, not in boys - a nationwide population-based study in Korea

Objectives

This study aimed to investigate the effect of rapid weight gain (RWG) on the incidence of central precocious puberty (CPP) using nationwide population-based data.

Methods

A total of 253,967 children (101,841 boys and 152,126 girls) who underwent regular health consultations under the National Health Insurance Service from 2007 to 2010 were followed up until the age of 10 years for boys and 9 years for girls. We calculated differences in the weight Z-scores from 4-6 months to 9-12 months (infancy) and from 9-12 months to 18-24 months or 30-36 months (toddlerhood) using the lambda-mu-sigma method. The population was subdivided into four groups: RWGinf/tod (infancy > + 0.67 standard deviation score [SDS], toddlerhood > 0 SDS), RWGinf (infancy > + 0.67 SDS, toddlerhood < 0 SDS), RWGtod (toddlerhood > + 0.67 SDS), and control (no RWG). The diagnosis of CPP was based on the diagnostic codes of the International Classification of Diseases 10th revision and the prescription of gonadotropin-releasing hormone agonists. The cumulative risk of CPP based on age was analyzed using Kaplan-Meier survival curves, and the association between the RWG groups and CPP was assessed using multivariate logistic regression analysis.

Results

CPP was diagnosed in 268 boys and 9,225 girls. For the girls, the CPP-free probability was the highest in the control group, followed by the RWGtod, RWGinf, and RWGinf/tod groups (log-rank p < 0.001). However, the incidence of CPP did not vary significantly for the boys. Compared to the control group, the other groups had a higher risk of CPP in girls (RWGinf/tod: adjusted odds ratio [aOR] 1.35, 95%, confidence interval [95% CI] 1.13-1.62; RWGinf: aOR 1.25, 95% CI 1.13-1.38; and RWGtod: aOR 1.18, 95% CI 1.09-1.28).

Conclusions

This nationwide population-based study demonstrated that any RWG from birth to 3 years of age contributed to an increased risk of CPP in girls but not in boys. Girls who experienced RWG during both infancy and toddlerhood had the highest risk of developing CPP. These findings suggest that early detection and appropriate management of excessive weight gain in early life may be important for preventing CPP in girls.

Approach to the Patient: Central Precocious Puberty

Central precocious puberty (CPP) classically refers to premature activation of the hypothalamic-pituitary-gonadal axis with onset of sexual development before the age of 8 years in girls and 9 years in boys. A decrease in the age of thelarche has been reported over the past several decades; however, the tempo of pubertal progression can be slower and adult height may not be adversely affected in many of the girls who experience thelarche at 6-8 years. Outside of this secular trend in the development itself, the past several decades have also brought about advances in diagnosis and management. This includes the widespread use of an ultrasensitive luteinizing hormone assay, decreasing the need for stimulation testing and a better understanding of the genetics that govern the onset of puberty. Additionally, management of CPP using gonadotropin-releasing hormone analogs (GnRHas) has changed with the advent of new longer-acting formulations. Emerging long-term outcomes of GnRHa administration with regards to obesity, cardiovascular risk factors and fertility are reassuring. Despite these advancements, clinical care in CPP is hampered by the lack of well-designed controlled studies, and management decisions are frequently not supported by clear practice guidelines. Data in boys with CPP are limited and this article focuses on the diagnosis and management of CPP in girls, particularly, in those who present with thelarche at the age of 6-8 years.

Persistent high exposure to exogenous phthalates and endogenous sex hormones associated with early pubertal onset among children: A 3.5-year longitudinal cohort study in China

BACKGROUND

Early onset of puberty could have significant impacts on childhood health, but the extent to which it was affected by phthalate esters (PAEs) and sex hormone disruption was not understood. The aim of this study is to investigate the associations between exposure to PAEs and sex hormone disruption and early onset of puberty in children.

METHODS

A longitudinal cohort study was conducted in China from May 2017 to Oct 2020, involving 740 children during consecutive visits. The onset of puberty was evaluated using Tanner definition, and early puberty was defined as an onset age less than the first 25 %, with cut-offs of 10.33 and 8.97 years for boys and girls, respectively. Serum testosterone (TT), estradiol (E₂) and urinary PAE metabolites were measured during three visits. Generalized linear models were used to explore the associations between PAE and sex hormones with the age of puberty onset, while log-binomial regressions were applied to assess the associations of persistent exposure to PAEs and sex hormones with early pubertal onset.

RESULTS

Approximately 86.0 % of boys and 90.2 % of girls completed puberty onset from pre-puberty, and more than 95 % of participants had PAE concentrations higher than the limit of detection. Boys showed higher exposure to PAE pollutants and higher TT levels. Persistent exposure to PAEs was positively associated with early pubertal onset in girls (ARR = 1.97, 95 %CI = 1.12, 3.46). Moreover, persistent exposure to PAEs and E₂ had synergistic associations with early pubertal onset in both boys (ARR = 4.77, 95 %CI = 1.06, 21.54) and girls (ARR = 7.07, 95 %CI = 1.51, 33.10). However, PAEs and TT had antagonistic associations only in boys (ARR = 0.44, 95 %CI = 0.07, 2.58).

CONCLUSION

Long-term exposure to PAEs might increase the risk of early pubertal onset, and it appears to work in synergy with E₂, while in antagonism with TT in boys' early pubertal onset. Reducing PAEs exposure might promote pubertal health.

Taking Stock: An Adaptable Research and Partnership Model for Developing Puberty Education in 10 Countries

There is a growing global interest in puberty and early adolescence and the importance of ensuring young people have the information and support they need during this critical phase of transition in the life course. This article highlights an adaptable model being used to support the development of contextually appropriate puberty education, in the form of illustrated and often bilingual books, for early adolescent girls and boys in countries around the world. This youth-centered participatory research and design model, which relies on the generation of community and government partnerships, has been employed in 10 countries thus far. Valuable learning has been documented from various contexts, including the approach's flexibility in adapting to the inputs of government and community members, incorporating local buy-in as a key ingredient for sustainability, using in-country experts for social and cultural appropriateness of illustrations and translations, and ensuring that the authentic youth voices captured through the participatory data collection and field-testing shape the educational content. The continuous integration of insights and perceptions of adults who influence young people's lives into the development process is also essential to enabling the uptake of puberty content in each new country. Parents, educators, youth service providers, and government officials are often the gatekeepers to young adolescents receiving puberty content and are thus critical to the process. This review of more than a decade of experience using this model underscores the essentiality of 2 key components-local partnership and participatory data collection-and highlights the importance of flexible approaches that are adapted to the unique sociocultural and environmental conditions in each country context.

Endocrine Health and Health Care Disparities in the Pediatric and Sexual and Gender Minority Populations: An Endocrine Society Scientific Statement

Endocrine care of pediatric and adult patients continues to be plagued by health and health care disparities that are perpetuated by the basic structures of our health systems and research modalities, as well as policies that impact access to care and social determinants of health. This scientific statement expands the Society's 2012 statement by focusing on endocrine disease disparities in the pediatric population and sexual and gender minority populations. These include pediatric and adult lesbian, gay, bisexual, transgender, queer, intersex, and asexual (LGBTQIA) persons. The writing group focused on highly prevalent conditions-growth disorders, puberty, metabolic bone disease, type 1 (T1D) and type 2 (T2D) diabetes mellitus, prediabetes, and obesity. Several important findings emerged. Compared with females and non-White children, non-Hispanic White males are more likely to come to medical attention for short stature. Racially and ethnically diverse populations and males are underrepresented in studies of pubertal development and attainment of peak bone mass, with current norms based on European populations. Like adults, racial and ethnic minority youth suffer a higher burden of disease from obesity, T1D and T2D, and have less access to diabetes treatment technologies and bariatric surgery. LGBTQIA youth and adults also face discrimination and multiple barriers to endocrine care due to pathologizing sexual orientation and gender identity, lack of culturally competent care providers, and policies. Multilevel interventions to address these disparities are required. Inclusion of racial, ethnic, and LGBTQIA populations in longitudinal life course studies is needed to assess growth, puberty, and attainment of peak bone mass. Growth and development charts may need to be adapted to non-European populations. In addition, extension of these studies will be required to understand the clinical and physiologic consequences of interventions to address abnormal development in these populations. Health policies should be recrafted to remove barriers in care for children with obesity and/or diabetes and for LGBTQIA children and adults to facilitate comprehensive access to care, therapeutics, and technological advances. Public health interventions encompassing collection of accurate demographic and social needs data, including the intersection of social determinants of health with health outcomes, and enactment of population health level interventions will be essential tools.

Changes in plasticity of the pelvic girdle from infancy to late adulthood in Homo sapiens

Previous research on the effects of body mass on the pelvic girdle focused mostly on adult females and males. Because the ontogenetic plasticity level in the pelvis remains largely unknown, this study investigated how the association between body mass index (BMI) and pelvic shape changes during development. It also assessed how the large variation in pelvic shape could be explained by the number of live births in females. Data included CT scans of 308 humans from infancy to late adulthood with known age, sex, body mass, body stature, and the number of live births (for adult females). 3D reconstruction and geometric morphometrics was used to analyze pelvic shape. Multivariate regression showed a significant association between BMI and pelvic shape in young females and old males. The association between the number of live births and pelvic shape in females was not significant. Less plasticity in pelvic shape in adult females than during puberty, perhaps reflects adaptation to support the abdominopelvic organs and the fetus during pregnancy. Non-significant susceptibility to BMI in young males may reflect bone maturation accelerated by excessive body mass. Hormonal secretion and biomechanical loading associated with pregnancy may not have a long-term effect on the pelvic morphology of females.

Aging and Pubertal Development Differentially Predict Symptoms of ADHD, Depression, and Impairment in Children and Adolescents: An Eight-Year Longitudinal Study

Activational effects of the reproductive neuroendocrine system may explain why some youths with ADHD are at greater risk for exacerbated ADHD symptoms (hyperactivity, inattention, impulsivity) during adolescence. For youths diagnosed with ADHD, first signs of ADHD symptoms become noticeable by multiple reporters (e.g., teachers, parents) when children enter schools, typically around kindergarten. The current study examined possible sex differences in ADHD, impairment, and comorbidity due to pubertal effects, as the role of pubertal development in ADHD is understudied. ADHD symptoms, depressive symptoms, impairment, and pubertal stage were assessed annually by multiple reporters in a well-characterized community sample of 849 children over-recruited for ADHD over eight years. Ages ranged from 7 to 13 years (38.16% female) at wave 1. Multilevel models indicated that males had higher levels of hyperactivity, impulsivity, and inattention than females, but that females had higher levels of impairment than males. Inattention symptoms did not show marked maturation changes. Hyperactivity and impulsivity declined as youth aged and impairment increased as youth aged. Lastly, depressive symptoms largely increased as youth aged and were higher amongst youth at later pubertal stages. Put together, aging and pubertal development are associated with improved ADHD symptoms but not for youth with high impairment. Findings from this study contributes to understanding the role that aging, pubertal status, and pubertal development plays in ADHD, impairment, and comorbidity in children and adolescents.

Association of size for gestational age and dehydroepiandrosterone sulfate with cardiometabolic risk in central precocious puberty girls

OBJECTIVE

The aim of this study was to assess whether size for gestational age and dehydroepiandrosterone sulfate (DHEAS) are associated with cardiometabolic risk in central precocious puberty (CPP) girls.

METHODS

The retrospective study included 443 patients with newly diagnosed CPP. Subjects were categorized by birth weight for gestational age (appropriate [AGA], small [SGA], and large [LGA] for gestational age) and serum DHEAS concentration (high [≥75th percentile] and normal [<75th percentile] DHEAS). Cardiometabolic parameters were examined. Composite cardiometabolic risk (CMR) score was calculated based on BMI, blood pressure, glucose, insulin, triglyceride, and HDL cholesterol. Non-obesity CMR score was computed, omitting the value from BMI. Logistic regression models, general linear models, and partial correlation analyses were used to evaluate associations. Propensity score matching was performed for sensitivity analyses.

RESULTS

Overall, 309 patients (69.8%) were born AGA, 80 (18.1%) were born SGA, and 54 (12.2%) were born LGA. Compared with AGA counterparts, CPP girls born SGA were more prone to have elevated HbA1c (adjusted OR = 4.54; 95% CI, 1.43-14.42) and low HDL cholesterol (adjusted OR = 2.33; 95% CI, 1.18-4.61). In contrast, being born LGA was not associated with increased risk for any glucose or lipid derangements. Despite the fact that elevated CMR score was more common among individuals born LGA than AGA (adjusted OR = 1.84; 95% CI, 1.07-4.35), no significant difference was found on non-obesity CMR score (adjusted OR = 0.75; 95% CI, 0.30-1.88). When controlling for age, birth weight SDS, and current BMI-SDS, individuals with high DHEAS exhibited higher HDL cholesterol and apolipoprotein A-1 concentrations and lower triglyceride level and non-obesity CMR score. Furthermore, DHEAS correlated positively with HDL cholesterol and apolipoprotein A-1 and negatively with triglyceride, prominently in girls born SGA, after adjustments for the three abovementioned confounders. Sensitivity analyses corroborated the findings.

CONCLUSION

Among CPP girls, those born SGA were more likely to possess cardiometabolic risk factors compared to their AGA peers. The difference we observed in cardiometabolic risk between individuals born LGA and AGA was driven by BMI. High DHEAS was associated with favorable lipid profile in CPP girls, even in subjects born SGA.

Associations of Obesity With Growth and Puberty in Children: A Cross-Sectional Study in Fuzhou, China

Objectives: To investigate the associations of obesity with growth and puberty in children. Methods: From November 2017 to December 2019, height, weight, and Tanner stages of 26,879 children aged 3-18 years in Fuzhou, China were assessed. Results: The obese group was significantly taller than the non-obese group after age 4 years for both genders, yet there was no significant difference in height between obese and non-obese group after 15.5 years old for boys and 12.5 years old for girls. The inflection points of significant growth deceleration in obese and non-obese groups were 14.4 and 14.6 years old for boys, and 11.8 and 12.8 years old for girls, respectively. The proportions of testicular development in boys with obesity and non-obesity were 7.96% and 5.08% at 8.5-8.9 years old, respectively, while the proportions of breast development in girls were 17.19% and 3.22% at age 7.5-7.9 years old, respectively. Conclusion: Children with obesity were taller in early childhood, earlier onset of puberty and earlier cessation of growth than children with non-obesity of the same age. However, there was sex dimorphism on the effect of obesity on the incidence of precocious puberty.

Obesity and menstrual disorders

Obesity is a growing public health concern and is associated with a range of menstrual disorders, including heavy menstrual bleeding, oligomenorrhea, dysmenorrhea, and endometrial pathology. Investigations may be more logistically challenging in those in the population with obesity, and because of the heightened risk of endometrial malignancy, there should be a low threshold for biopsy to exclude endometrial hyperplasia. Although treatment modalities for women with obesity are broadly similar to those with a normal BMI, additional consideration must be given to the risks associated with estrogen in obesity. Outpatient management of heavy menstrual bleeding is a developing field and outpatient treatment modalities are preferable in the population with obesity to avoid the morbidity associated with anesthetics.

National survey of referrals for precocious puberty in Germany

An unusual high number of girls were referred to our paediatric endocrine clinic with suspected precocious puberty (PP) since the beginning of the COVID-19 pandemic. We analysed our data and initiated a survey among German paediatric endocrinologists.At our centre, less than 10 patients were diagnosed of PP annually between 2015 and 2019. This increased to n=23 (2020) and n=30 (2021). A German survey confirmed this observation: Out of 44 centres which completed the questionnaire, 30/44 (68%) reported an increase of PP. Above this, 32/44 (72%) stated an increase in girls diagnosed with 'early normal puberty' since the beginning of the COVID-19 pandemic.

Differential diagnosis of precocious puberty in girls during the COVID-19 pandemic: a pilot study

BACKGROUND

To investigate the differential diagnosis of girls aged 6 to 8 years with idiopathic premature thelarche (IPT) and central precocious puberty (CPP) during the COVID-19 pandemic. We explored predicted adult height (PAH) discrepancy to guide appropriate diagnosis and treatment.

METHODS

From January 2020 to December 2021, Chinese girls aged 6 to 8 years with precocious puberty were recruited. They were divided into IPT and CPP groups. Clinical characteristics, including height, weight, body mass index (BMI), basal luteinizing hormone (LH), oestradiol, uterine length and volume, follicle numbers (d > 4 mm) and bone age (BA) were recorded. We analysed differential diagnosis and PAH discrepancy in both groups. Binary logistic regression analysis was used to explore risk factors for CPP, and receiver operating characteristic (ROC) curves were generated to evaluate the diagnostic value of related indexes.

RESULTS

Sixty patients, including 40 girls with IPT and 20 girls with CPP, were recruited. The prevalence of overweight and obesity in the entire cohort was 25% (15/60) and was significantly higher in IPT than CPP, 32.5% (13/40) vs. 10% (2/20), respectively (P=0.045). There were significant differences in LH, uterine volume, follicle numbers and BA (P<0.05). The impaired PAH of IPT and CPP was 0.01 ± 1.19 SD and 0.62 ± 0.94 SD with significant differences (P=0.047). Logistic regression analysis showed that LH and follicle numbers were independent risk factors for CPP. The ROC curve showed that the area under the curve (AUC) of LH and follicle numbers were 0.823 and 0.697. The sensitivity and specificity of LH with a cut off of 0.285 IU/L were 78.9% and 77.8%. The sensitivity and specificity of follicle numbers with a cut off of 3.5 were 89.5% and 52.8%.

CONCLUSION

The prevalence of overweight and obesity in 6- to 8-year-old girls with precocious puberty was high. Auxological data should not be used in the differential diagnosis of IPT and CPP. Basal LH above 0.285 IU/L and follicle numbers greater than 4 were important features suggestive of CPP. PAH was impaired in individuals with CPP, but it was not impaired in individuals with IPT.

Parental factors that impact the ecology of human mammary development, milk secretion, and milk composition-a report from "Breastmilk Ecology: Genesis of Infant Nutrition (BEGIN)" Working Group 1

The goal of Working Group 1 in the Breastmilk Ecology: Genesis of Infant Nutrition (BEGIN) Project was to outline factors influencing biological processes governing human milk secretion and to evaluate our current knowledge of these processes. Many factors regulate mammary gland development in utero, during puberty, in pregnancy, through secretory activation, and at weaning. These factors include breast anatomy, breast vasculature, diet, and the lactating parent's hormonal milieu including estrogen, progesterone, placental lactogen, cortisol, prolactin, and growth hormone. We examine the effects of time of day and postpartum interval on milk secretion, along with the role and mechanisms of lactating parent-infant interactions on milk secretion and bonding, with particular attention to the actions of oxytocin on the mammary gland and the pleasure systems in the brain. We then consider the potential effects of clinical conditions including infection, pre-eclampsia, preterm birth, cardiovascular health, inflammatory states, mastitis, and particularly, gestational diabetes and obesity. Although we know a great deal about the transporter systems by which zinc and calcium pass from the blood stream into milk, the interactions and cellular localization of transporters that carry substrates such as glucose, amino acids, copper, and the many other trace metals present in human milk across plasma and intracellular membranes require more research. We pose the question of how cultured mammary alveolar cells and animal models can help answer lingering questions about the mechanisms and regulation of human milk secretion. We raise questions about the role of the lactating parent and the infant microbiome and the immune system during breast development, secretion of immune molecules into milk, and protection of the breast from pathogens. Finally, we consider the effect of medications, recreational and illicit drugs, pesticides, and endocrine-disrupting chemicals on milk secretion and composition, emphasizing that this area needs much more research attention.

Association between early life adversity and allostatic load in girls with precocious puberty

CONTEXT

The mechanisms underlying the elevated long-term health risk in girls with precocious puberty remain unclear, but might result from physiological wear and tear associated with greater exposure to early life adversity.

OBJECTIVE

This study aims to explore early life adversity in girls with precocious puberty and its association with allostatic load.

METHODS

Early life adversity and hair cortisol concentration were measured among 213 girls with precocious puberty (8.21 ± 1.07). Allostatic load score is constructed by using 13 physiological biomarkers representing four systems and hair cortisol concentration. Multivariate linear regression models have estimated the associations between cumulative early life adversity exposure with total and system-specific allostatic load scores. Associations between cumulative early life adversity and the risk of high allostatic load (3 + high-risk biomarkers) were tested using binary logistics regression.

RESULTS

More than two-thirds (67.6%) of girls with central precocious puberty reported two or more early life adversity exposure. Compared to those with no early life adversity exposure, girls who reported early life adversity score ≥ 2 had significantly higher total allostatic load score (β: 1.20-1.64, P < 0.001). Metabolic system was more sensitive to cumulative early life adversity exposure, each form of early life adversity exposure was associated with 0.48-unit increases in metabolic allostatic load score (95%CI: 0.06, 0.90, P = 0.026). Girls reported early life adversity score ≥ 3 were three times more likely to have a high allostatic load compared with those without early life adversity exposure in both unadjusted and adjusted models (OR_adjusted=3.83, 95%CI: 1.17, 12.55, P = 0.001).

CONCLUSION

Multisystem physiological dysregulation is observed in girls with central precocious puberty, which might result from cumulative wear-and-tear associated with early life adversity.

Pubertal induction in Turner syndrome without gonadal function: A possibility of earlier, lower-dose estrogen therapy

Delayed and absent puberty and infertility in Turner syndrome (TS) are caused by primary hypogonadism. A majority of patients with TS who are followed at hospitals during childhood will not experience regular menstruation. In fact, almost all patients with TS need estrogen replacement therapy (ERT) before they are young adults. ERT in TS is administered empirically. However, some practical issues concerning puberty induction in TS require clarification, such as how early to start ERT. The present monograph aims to review current pubertal induction therapies for TS without endogenous estrogen production and suggests a new therapeutic approach using a transdermal estradiol patch that mimics incremental increases in circulating, physiological estradiol. Although evidence supporting this approach is still scarce, pubertal induction with earlier, lower-dose estrogen therapy more closely approximates endogenous estradiol secretion.

Normative body image development: A longitudinal meta-analysis of mean-level change

This meta-analysis synthesized longitudinal data on mean-level change in body image, focusing on the constructs of body satisfaction and dissatisfaction, body esteem, perceived attractiveness, valuation, self-objectification, and body shame. We searched five databases and accessed unpublished data to identify studies that assessed body image at two or more time points over six months or longer. Analyses were based on data from 142 samples representing a total of 128,254 participants. The age associated with the midpoint of measurement intervals ranged from 6 to 54 years. Multilevel metaregression models examined standardized yearly mean change, and the potential moderators of body image construct, gender, birth cohort, attrition rate, age, and time lag. Boys and men showed fluctuations in overall body image with net-improvements between ages 10 and 24. Girls and women showed worsening body image between ages 10 and 16, but improvements between ages 16 and 24. Change was greatest between ages 10 and 14, and stabilized around age 24. We found no effect of construct, birth cohort, or attrition rate. Results suggest a need to revise understandings of normative body image development: sensitive periods may occur somewhat earlier than previously believed, and body image may show mean-level improvements during certain age ranges.

Asthma occurrence in children and early life systemic antibiotic use: an incidence density study

BACKGROUND

Results of studies evaluating the relationship between asthma occurrence and early life antibiotic use have been conflicting. The aim of this study was to investigate the relationship between occurrence of asthma in children and systemic antibiotic use in the first year of life based on an incidence density study with careful consideration of the temporal aspects of the determinant-outcome relationship.

METHODS

We conducted an incidence density study nested in a data collection project with information on 1128 mother-child pairs. Systemic antibiotic use in the first year of life was defined as excessive (≥ 4 courses) vs. non-excessive (< 4 courses) use based on information from weekly diaries. Events (cases) were defined as the first parent-reported occurrence of asthma in a child between 1 and 10 years of age. Population time 'at risk' was probed by sampling population moments (controls). Missing data were imputed. Multiple logistic regression was used to assess the association between current first asthma occurrence (incidence density) and systemic antibiotic use in the first year of life, to evaluate effect modification and adjust for confounding.

RESULTS

Forty-seven first asthma events and 147 population moments were included. Excessive systemic antibiotic use in the first year of life showed more than twice the incidence density of asthma compared to non-excessive use (adjusted IDR [95% CI]: 2.18 [0.98, 4.87], p = 0.06). The association was more pronounced in children who have had lower respiratory tract infections (LRTIs) in the first year of life compared to children who had no LRTIs in the first year of life (adjusted IDR [95% CI]: 5.17 [1.19, 22.52] versus 1.49 [0.54, 4.14]).

CONCLUSIONS

Excessive use of systemic antibiotics in the first year of life may play a role in the genesis of asthma in children. This effect is modified by the occurrence of LRTIs in the first year of life, with a stronger association observed in children experiencing LRTIs in the first year of life.

The Congenital and Acquired Mechanisms Implicated in the Etiology of Central Precocious Puberty

The etiology of central precocious puberty (CPP) is multiple and heterogeneous, including congenital and acquired causes that can be associated with structural or functional brain alterations. All causes of CPP culminate in the premature pulsatile secretion of hypothalamic GnRH and, consequently, in the premature reactivation of hypothalamic-pituitary-gonadal axis. The activation of excitatory factors or suppression of inhibitory factors during childhood represent the 2 major mechanisms of CPP, revealing a delicate balance of these opposing neuronal pathways. Hypothalamic hamartoma (HH) is the most well-known congenital cause of CPP with central nervous system abnormalities. Several mechanisms by which hamartoma causes CPP have been proposed, including an anatomical connection to the anterior hypothalamus, autonomous neuroendocrine activity in GnRH neurons, trophic factors secreted by HH, and mechanical pressure applied to the hypothalamus. The importance of genetic and/or epigenetic factors in the underlying mechanisms of CPP has grown significantly in the last decade, as demonstrated by the evidence of genetic abnormalities in hypothalamic structural lesions (eg, hamartomas, gliomas), syndromic disorders associated with CPP (Temple, Prader-Willi, Silver-Russell, and Rett syndromes), and isolated CPP from monogenic defects (MKRN3 and DLK1 loss-of-function mutations). Genetic and epigenetic discoveries involving the etiology of CPP have had influence on the diagnosis and familial counseling providing bases for potential prevention of premature sexual development and new treatment targets in the future. Global preventive actions inducing healthy lifestyle habits and less exposure to endocrine-disrupting chemicals during the lifespan are desirable because they are potentially associated with CPP.

Secular trend and urban-rural disparity for age at spermarche among Chinese Han boys from 1995 to 2019

AIM

To examine the secular trend and the urban-rural disparity of spermarche among Chinese Han boys from 1995 to 2019.

METHODS

A total of 392 775 boys of Han ethnicity aged 11-18 years were extracted from the 1995, 2000, 2005, 2010, 2014 and 2019 Chinese National Surveys on Students' Constitution and Health. The median age at spermarche was estimated using the status quo data and probit analysis. The chi-square, ANOVA and LSD tests were used to compare the differences between the year-subgroups. U-test was used to compare the difference between urban and rural areas at each year.

RESULTS

The median age at spermarche in Chinese Han boys decreased from 14.6 years in 1995 to 13.9 years in 2019 (p < 0.001). The rural boys showed a faster decreasing pace with a 1-year advance of age at spermarche while the urban boys had only a 0.5-year decrement, and there was still a statistically significant difference between urban-rural areas in 2019 (p < 0.001). Similar to urban-rural disparity, the age gap at spermarche between areas with different urbanisation rates became smaller over time.

CONCLUSIONS

In general, spermarche in Chinese Han boys showed a decreasing trend, but the pace was slowing down. The urban-rural disparity in puberty development still existed but was gradually narrowing.

Neighborhood Racial and Economic Privilege and Timing of Pubertal Onset in Girls

PURPOSE

Early puberty is associated with adverse health outcomes over the life course, and Black and Hispanic girls experience puberty earlier than girls of other racial/ethnic backgrounds. Neighborhood racial and economic privilege may contribute to these disparities by conferring differential exposure to mechanisms (e.g., stress, obesity, endocrine disruptors) underlying early puberty. We examined associations between neighborhood privilege, measured by the Index of Concentration at the Extremes (ICE), and age at pubic hair onset (pubarche) and breast development onset (thelarche) in a large multiethnic cohort.

METHODS

A cohort of 46,299 girls born 2005-2011 at Kaiser Permanente Northern California medical facilities were followed until 2021. Pubertal development was assessed routinely by pediatricians using the Sexual Maturity Rating scale. ICE quintiles for race/ethnicity, income, and income + race/ethnicity were calculated using American Community Survey 2010 5-year estimates and linked to census tract at birth. We fit multilevel Weibull regression models accommodating left, right, and interval censoring for all analyses.

RESULTS

ICE measures were monotonically associated with pubertal onset, with the strongest associations observed for ICE-race/ethnicity. Adjusting for maternal education, age at delivery, and parity, girls from the least versus most privileged ICE-race/ethnicity quintiles were at increased risk for earlier pubarche (hazard ratio: 1.30, 95% confidence interval: 1.21, 1.38) and thelarche (hazard ratio: 1.45, 95% confidence interval: 1.36, 1.54). These associations remained significant after adjusting for girls' race/ethnicity and childhood body mass index. Additionally, adjustment for ICE partially attenuated Black-White and Hispanic-White disparities in pubertal onset.

DISCUSSION

Neighborhood privilege may contribute to pubertal timing and related disparities.

Molecular basis of normal and pathological puberty: from basic mechanisms to clinical implications

Puberty is a major maturational event; its mechanisms and timing are driven by genetic determinants, but also controlled by endogenous and environmental cues. Substantial progress towards elucidation of the neuroendocrine networks governing puberty has taken place. However, key aspects of the mechanisms responsible for the precise timing of puberty and its alterations have only recently begun to be deciphered, propelled by epidemiological data suggesting that pubertal timing is changing in humans, via mechanisms that are not yet understood. By integrating basic and clinical data, we provide a comprehensive overview of current advances on the physiological basis of puberty, with a particular focus on the roles of kisspeptins and other central transmitters, the underlying molecular and endocrine mechanisms, and the pathways involved in pubertal modulation by nutritional and metabolic cues. Additionally, we have summarised molecular features of precocious and delayed puberty in both sexes, as revealed by clinical and genetic studies. This Review is a synoptic up-to-date view of how puberty is controlled and of the pathogenesis of major pubertal alterations, from both a clinical and translational perspective. We also highlight unsolved challenges that will seemingly concentrate future research efforts in this active domain of endocrinology.

Bone age assessment: Large-scale comparison of Greulich-Pyle method and Tanner-Whitehouse 3 method for Taiwanese children

BACKGROUND

The Greulich-Pyle (GP) and Tanner-Whitehouse 3 (TW3) methods are two common methods for assessing bone age (BA). The applicability of these methods for populations other than those in the United States and Europe has been questioned. Thus, this study tested the applicability of these methods for Taiwanese children.

METHODS

In total, 1476 radiographs (654 boys, 822 girls) were analyzed. A subset of 200 radiographs was evaluated to determine intrarater and interrater reliability and the time required to yield a BA assessment. BA was determined by two reviewers using the GP method and two of the TW3 methods (the Radial-Ulnar-Short bones [RUS] method and the carpals method [Carpal]). The GP and TW3 methods were directly compared using statistical techniques. A subgroup analysis by age was performed to compare BA and chronological age using a paired t test for each age group.

RESULTS

The average times required to yield an assessment using the GP and TW3-RUS methods were 0.79 ± 0.14 and 3.01 ± 0.84 min (p < 0.001), respectively. Both the intrarater and interrater correlation coefficients were higher for the GP method (0.993, 0.992) than the TW3-RUS (0.985, 0.984) and TW3-Carpal (0.981, 0.973) methods. The correlation coefficient for the GP and TW3-RUS methods was highest in the pubertal stage (0.898 for boys and 0.909 for girls). The mean absolute deviations for the GP and TW3-RUS methods in the pubertal stage were 0.468 years (boys) and 0.496 years (girls). Both the GP and TW3-Carpal methods underestimated BA for boys in the prepubertal stage. Both the GP and TW3-RUS methods overestimated BA for girls in the pubertal and postpubertal stages.

CONCLUSION

The GP and TW3-RUS methods exhibit strong agreement in the pubertal and postpubertal stages for both sexes. With appropriate adjustments based on Taiwanese data, both methods are applicable to our children.

Effects of half-dose spiomet treatment in girls with early puberty and accelerated bone maturation: a multicenter, randomized, placebo-controlled study protocol

BACKGROUND

A "mismatch" sequence of less prenatal weight gain and more postnatal weight gain may lead to ectopic lipid accumulation, and trigger the development of early adrenarche/pubarche and the activation of the gonadotropic axis resulting in early puberty and ending up in full-blown adolescent polycystic ovary syndrome (PCOS). In the present study, we assess whether a low-dose combination of generics that collectively reduce ectopic fat through different pathways can slow down the accelerated maturation in "mismatch" girls with early puberty.

METHODS

Randomized, placebo-controlled, multicenter, phase 2a, study in 64 girls [age, 8.0-9.3 years; birthweight (BW) for gestational age in lower tertile (-1.96< Z-score <-0.44), body mass index (BMI) in upper tertile (+0.44< Z-score < +1.96) and early progressive puberty (Tanner B2 at 7.7-9.0 years)]. Pharmacological intervention will be with a half-dose version of SPIOMET (mini-spiomet), a combination that reverts the PCOS phenotype in "mismatch" adolescents; mini-spiomet will contain spironolactone (25 mg/day, to raise brown adipose tissue activity), pioglitazone (3.75 mg/day, to raise adiponectin and insulin sensitivity), and metformin (425 mg/day, to raise AMPK activity and GDF15). Recruitment: 1 year; double-blind treatment: 1 year; open follow-up: 1 year; analyses and reporting: 1 year.

INTERVENTIONS

randomization (1:1) for placebo vs mini-spiomet.

PRIMARY OUTCOME

annualized bone age advancement (0-1 year) by BoneXpert; secondary outcomes: insulin, IGF-I, high-molecular-weight adiponectin (HMW-adip), sex hormone binding globulin (SHBG), ultra-sensitive C-reactive protein (usCRP), androgens, luteinizing hormone (LH), follicle-stimulating hormone (FSH), oestradiol, growth-and-differentiation factor 15 (GDF15), C-X-C motif chemokine ligand-14 (CXCL14), safety parameters, and quantification of hepato-visceral fat.

DISCUSSION

The present study, if successful, may provide a first proof of the concept that the rapid maturation of girls with an upward mismatch between pre- and post-natal weight gain can be slowed down with a fixed low-dose combination of old and safe generics jointly targeting a reduction of ectopic fat without necessarily lowering body weight.

TRIAL REGISTRATION

EudraCT 2021-006766-21. Registered on May 30, 2022.

Pattern of linear growth and progression of bone maturation for girls with early-onset puberty: A mixed longitudinal study

Background and objective

With a worldwide trend to earlier age of onset of puberty, the prevalence of early-onset puberty (EP) among girls has increased. The impact of EP on the pattern of linear growth and bone maturation is unclear. Accordingly, the objective of our study was to describe this pattern for girls with EP in Shenzhen, China.

Methods

A total of 498 untreated girls diagnosed with EP at Shenzhen Children's Hospital, China, between January 2016 and December 2021. A total of 1,307 anthropometric measurements and 1,307 left-hand radiographs were available for analysis. Artificial intelligence (AI) was used to determine bone age (BA). Participants were classified into groups according to chronological age (CA) and BA. The pattern of linear growth (height) and progression of bone maturation was described between groups using the Lambda-Mu-Sigma (LMS) method. Published height-for-CA and height-for-BA norm references for a healthy Chinese population were used for age-appropriate comparisons.

Results

The mean CA of appearance of first pubertal signs (breast buds) was 8.1 ± 0.5 years. Compared to norm-referenced data, girls with EP were significantly taller at a CA of 7-10 years. This was followed by a slowing in linear growth after a CA of 10 years, with 71 girls with EP having already achieved their target adult height. From 7 to 10 years of BA, the linear growth was slower in the EP group compared to norm-reference values. This was followed by a period of catch-up growth at 11.2 years of BA, with growth curves approaching norm-referenced values. The BA progressed rapidly from 7 to 8 years of age in about half of the girls with EP (median ΔBA/ΔCA >1.9), slowing, thereafter, until the period of catch-up growth at 11.2 years of BA.

Conclusions

BA provides a more reliable reference than CA to assess growth parameters among girls with EP. Our limited data set does indicate that EP does not negatively impact final adult height. Therefore, the growth curves from our study are relevant, providing a reference for pediatricians in this clinical population and, thus, preventing over-treatment for EP.

Ongoing increasing trends in central precocious puberty incidence among Korean boys and girls from 2008 to 2020

BACKGROUND

Over the last few decades, there has been growing evidence of earlier onset and progression of puberty worldwide. This population-based longitudinal cohort study aimed to analyze the change in the annual incidence rate of central precocious puberty (CPP) among Korean children over the most recent decade, using the national registry data.

METHOD

The International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) and insurance claims for gonadotropin-releasing hormone agonist (GnRHa) treatment were used to identify CPP patients who were using the Korean Health Insurance Review & Assessment Service (HIRA) database between 2008 and 2020. Patients who began GnRHa therapy before the age of 9 and 10 for girls and boys, respectively, were included in the study.

RESULTS

A total of 6,906 boys and 126,377 girls were diagnosed with CPP between 2008 and 2020. The annual incidence of CPP increased by 83.3 times in boys (from 1.2 to 100 per 100,000 persons) and by 15.9 times in girls (from 88.9 to 1414.7 per 100,000 persons). The age-specific annual incidence of CPP increased remarkably more in older children than in younger ones; the 2020 CPP incidence among 9-year-old boys and 8-year-old girls reached 705.2 and 7,967.3 per 100,000 persons, respectively. The annual prevalence of CPP in boys and girls increased from 2.7 to 206.5 (76.5 times) and from 141.8 to 3439.9 (24.3 times) per 100,000 persons, respectively.

CONCLUSION

Based on GnRHa treatment insurance claims, our study suggests that the annual incidence of CPP has substantially increased in Korea during the past 13 years. These findings highlight the importance of meticulous judgment by doctors in determining GnRHa treatment.

Did Stress Prevalence Among Adolescents in Scandinavia Change from 2000 to 2019? A literature review

Background

Prolonged stress is a risk factor for developing mental illness and stress-related diseases. As there has been an increase in self-reported psychological symptoms and diagnosis of mental illness among Scandinavian adolescents, more knowledge of stress prevalence in this age group is needed.

Aim

This literature review will investigate a possible increase in stress prevalence among Scandinavian adolescents, aged 13-18, between the years 2000 and 2019.

Methods

A systematic literature search was conducted in the PubMed and PsycInfo databases. In addition, a grey literature search was conducted to find relevant surveys and reports. Altogether, nine papers and nine surveys, and reports containing relevant data were identified, assessed for risk of bias, and included in the analysis.

Results

The results show higher stress scores among the older participants in the age group 13-18 years and a gender difference, where girls score higher than boys. The literature neither supports nor rejects the hypothesis that stress levels have increased among adolescents in Scandinavia, from year 2000 to 2019. Only two of the included studies used a validated stress questionnaire and there was a substantial risk of non-response bias. Therefore, the existing literature is considered insufficient to determine if there has been an increase in stress over time. A majority of the papers, surveys, and reports had moderate risk of bias.

Conclusions

Further research using validated stress questionnaires in representative populations is needed to investigate changes in stress prevalence among Scandinavian adolescents. Also, the age and gender difference in stress prevalence among 13-18-year-olds may be of relevance for planning preventive interventions to reduce stress.

Neuroimaging in 205 consecutive Children Diagnosed with Central Precocious Puberty in Denmark

INTRODUCTION

A brain magnetic resonance image (MRI) is considered part of routine evaluation in children diagnosed with central precocious puberty (CPP) to rule out intracranial pathology. We evaluated the occurrence of pathological findings on neuroimaging among children diagnosed with CPP.

METHODS

A retrospective study based on an evaluation of 1544 children referred with early signs of puberty from 2009-2019. Of these, 205 children (29 boys) with confirmed CPP had a brain MRI performed, and we report MRI results, pubertal stage, bone age, and hormonal analyses. All abnormal MRI results were re-evaluated by a trained neuroradiologist.

RESULTS

A new intracranial pathology was found by brain MRI in 6 out of 205 patients aged 1.5 to 6.1 years. The occurrence of intracranial pathology was 3/162 (1.8%) and 3/24 (12.5 %) in girls and boys respectively.

CONCLUSION

Organic causes of precocious puberty are more frequent in boys with CPP than in girls. No cases of organic CPP were seen above age 6.1 years of age. The age cut off value for routine brain MRI could be lowered to seven or perhaps even six years of age for girls, except in rapidly progressing puberty or presence of neurological symptoms.

IMPACT

In our study of children with central precocious puberty (CPP), intracranial pathology is a rare cause and occurs only in younger children. It supports the general trend, that younger children are at higher risk of having organic causes to CPP and supports the clinical practice, that only high-risk patients with CPP should undergo routine brain MRI.

Precocious puberty under stressful conditions: new understanding and insights from the lessons learnt from international adoptions and the COVID-19 pandemic

Neuro-biological variations in the timing of sexual maturation within a species are part of an evolved strategy that depend on internal and external environmental conditions. An increased incidence of central precocious puberty (CPP) has been described in both adopted and "covid-19 pandemic" children. Until recently, it was hypothesised that the triggers for CPP in internationally adopted children were likely to be better nutrition, greater environmental stability, and improved psychological wellbeing. However, following data collected during and after the coronavirus (COVID-19) global pandemic, other possibilities must be considered. In a society with high levels of child wellbeing, the threat to life presented by an unknown and potentially serious disease and the stressful environment created by lockdowns and other public health measures could trigger earlier pubertal maturation as an evolutionary response to favour early reproduction. The main driver for increased rates of precocious and rapidly progressive puberty during the pandemic could have been the environment of "fear and stress" in schools and households. In many children, CPP may have been triggered by the psychological effects of living without normal social contact, using PPE, being near adults concerned about financial and other issues and the fear of getting ill. The features and time of progression of CPP in children during the pandemic are similar to those observed in adopted children. This review considers the mechanisms regulating puberty with a focus on neurobiological and evolutionary mechanisms, and analyses precocious puberty both during the pandemic and in internationally adopted children searching for common yet unconsidered factors in an attempt to identify the factors which may have acted as triggers. In particular, we focus on stress as a potential factor in the early activation of the hypothalamic-pituitary-gonadal axis and its correlation with rapid sexual maturation.

Regional variation in growth status: A cross-sectional survey among Tibetan adolescents living at three different high altitudes in Tibet, China

OBJECTIVE

To explore the regional and age variation in growth status and age-by-site interaction effect on the growth status among Chinese Tibetan adolescents at different altitudes in Tibet, China.

METHODS

The research was conducted in three regions of Tibet, China: Nyingchi (average altitude 3100 m), Lhasa (average altitude 3650 m), and Nagqu (average altitude 4500 m). A total of 3817 Chinese Tibetan adolescents aged 12-18 years were tested for height, weight, chest circumference, and waist circumference. One-way ANOVA was used to compare the growth status of Chinese Tibetan adolescents. Two-way ANOVA was used to explore the age-by-site interaction effect on the growth status of Chinese Tibetan adolescents.

RESULTS

The height, weight, and chest circumference of Chinese Tibetan adolescents in Nagqu are the lowest among the three cities. Age and site have an interaction effect influence on the growth status of Chinese Tibetan adolescents (p < .01).

CONCLUSIONS

The growth indicators (height, weight, chest circumference, WC) of Chinese Tibetan adolescents differed with altitudes. Policies to improve the growth status of Chinese Tibetan adolescents in Nagqu are urgently needed.

Combined assisted bone age assessment and adult height prediction methods in Chinese girls with early puberty: analysis of three artificial intelligence systems

BACKGROUND

The applicability and accuracy of artificial intelligence (AI)-assisted bone age assessment and adult height prediction methods in girls with early puberty are unknown.

OBJECTIVE

To analyze the performance of AI-assisted bone age assessment methods by comparing the corresponding methods for predicted adult height with actual adult height.

MATERIALS AND METHODS

This retrospective review included 726 girls with early puberty, 87 of whom had reached adult height at last follow-up. Bone age was evaluated using the Greulich-Pyle (GP), Tanner-Whitehouse (TW3-RUS) and China 05 RUS-CHN (RUS-CHN) methods. Predicted adult height was calculated using the China 05 (CH05), TW3 and Bayley-Pinneau (BP) methods.

RESULTS

We analyzed 1,663 left-hand radiographs, including 155 from girls who had reached adult height. In the 6-8- and 9-11-years age groups, bone age differences were smaller than those in the 12-14-years group; however, the differences between predicted adult height and actual adult height were larger than those in the 12-14-years group. TW3 overestimated adult height by 0.4±2.8 cm, while CH05 and BP significantly underestimated adult height by 2.9±3.6 cm and 1.3±3.8 cm, respectively. TW3 yielded the highest proportion of predicted adult height within ±5 cm of actual adult height (92.9%), with the highest correlation between predicted and actual adult heights.

CONCLUSION

The differences in measured bone ages increased with increasing bone age. However, the corresponding method for predicting adult height was more accurate when the bone age was older. TW3 might be more suitable than CH05 and BP for predicting adult height in girls with early puberty. Methods for predicting adult height should be optimized for populations of the same ethnicity and disease.

Association between healthy lifestyle pattern and early onset of puberty: based on a longitudinal follow-up study

The present study aimed to explore the association between healthy lifestyle pattern and childhood early onset of puberty. Based on a cohort study in Xiamen of China, a total of 1294 children was followed for three and a half years. Children's lifestyles, including dietary behaviour, physical activity, sleep duration, smoking and drinking behaviour and sedentary behaviour, were collected by questionnaires. Healthy lifestyle pattern was determined mainly according to the recommendations by the Dietary Guidelines for Chinese school-age children and Canadian Guidelines for children and youth. The pubertal development was assessed by clinical examination according to Tanner stages. The association between pre-pubertal lifestyle and early onset of puberty was estimated using linear regression and log-binomial regression. We found that children who adhered to a healthy lifestyle had a 0·36-year delay of the age of puberty onset (coef = 0·36, 95 % CI (0·08, 0·65)) and 53 % lower risk of early onset of puberty (risk ratio = 0·47, 95 % CI (0·27, 0·80)), compared with those who had a poor lifestyle. However, the beneficial effect of favourable lifestyles on the early onset of puberty was found only in boys with normal weight. Boys who adhered to active physical activity and low sedentary behaviour had a relatively delayed age of puberty onset (coef = 0·49, 95 % CI (0·26, 0·72)). This is the first time to find that healthy lifestyle pattern was associated with a substantially lower risk of early onset of puberty, especially in boys with normal weight. Advocating an integrated healthy lifestyle is essential for the development of children.

Gonadotropin-releasing hormone analogue and recombinant human growth hormone treatment for idiopathic central precocious puberty in girls

PURPOSE

To investigate the effectiveness and safety of gonadotropin-releasing hormone analogue (GnRHa) in combination with recombinant human growth hormone (rhGH) in girls with central precocious puberty (CPP).

METHODS

Clinical data of 80 girls diagnosed with idiopathic central precocious puberty (ICPP) between January 2017 and June 2021 were retrospectively analyzed. Treatment strategy involved GnRHa alone (group A: n=34) and GnRHa+rhGH (group B: n=46). Children's heights (Ht), weights (Wt) and sex hormone levels were measured every 3 months after treatment and bone age (BA) every six months. Heights, growth velocity (GV), predicted adult height (PAH), weights, body mass index (BMI), sex hormone levels and bone age were compared between the two groups.

RESULTS

Children in group B showed greater height gain at the 12th, 24th and 30th months after treatment (p<0.05) than those in group A, had faster growth rates in the first and second year following treatment (p<0.05) and better PAH (p<0.05). No statistical differences in weight or BMI were found between the two groups before treatment or at any time after treatment (p>0.05). Levels of LH and FSH were lower in both groups after treatment with no statistical differences between groups (p>0.05). The gap between bone age and chronological age gradually decreased in both groups and no abnormal progression of bone age or other adverse side effects occurred.

CONCLUSIONS

The combination of GnRHa with rhGH produced better height gains than GnRHa alone for patients with CPP. The gonadal axis was suppressed and progression of bone age delayed with good safety and efficacy.

Bring the life stages into the domain of basic and clinical pharmacology

Completely distinct physiological conditions and immune responses exist among different human life stages. Age is not always consistent with the life stage. We proposed to incorporate the concept of the life stages into basic and clinical pharmacology, including clinical trials, drug labels, and drug usage in clinical practice. Life-stage-based medical treatment is the application of medicine according to life stages such as prepuberty, reproductive, and aging. A large number of diseases are life-stage-dependent. Many medications and therapy have shown various age effects but not been recognized as life-stage-dependent. The same dosage and drug applications used in different life stages lead to divergent outcomes. Incorporating life stages in medicine and drug usage will enhance the efficacy and precision of the medication in disease treatment.

Chemical Effects on Breast Development, Function, and Cancer Risk: Existing Knowledge and New Opportunities

Population studies show worrisome trends towards earlier breast development, difficulty in breastfeeding, and increasing rates of breast cancer in young women. Multiple epidemiological studies have linked these outcomes with chemical exposures, and experimental studies have shown that many of these chemicals generate similar effects in rodents, often by disrupting hormonal regulation. These endocrine-disrupting chemicals (EDCs) can alter the progression of mammary gland (MG) development, impair the ability to nourish offspring via lactation, increase mammary tissue density, and increase the propensity to develop cancer. However, current toxicological approaches to measuring the effects of chemical exposures on the MG are often inadequate to detect these effects, impairing our ability to identify exposures harmful to the breast and limiting opportunities for prevention. This paper describes key adverse outcomes for the MG, including impaired lactation, altered pubertal development, altered morphology (such as increased mammographic density), and cancer. It also summarizes evidence from humans and rodent models for exposures associated with these effects. We also review current toxicological practices for evaluating MG effects, highlight limitations of current methods, summarize debates related to how effects are interpreted in risk assessment, and make recommendations to strengthen assessment approaches. Increasing the rigor of MG assessment would improve our ability to identify chemicals of concern, regulate those chemicals based on their effects, and prevent exposures and associated adverse health effects.

Prenatal nitrate exposure from diet and drinking water and timing of puberty in sons and daughters: A nationwide cohort study

BACKGROUND

In Western countries, age at pubertal development has declined during the last century in girls, and probably also in boys. No studies have investigated whether nitrate, a widespread environmental exposure with teratogenic and hormone disrupting properties, might affect timing of puberty.

OBJECTIVES

We investigated if prenatal exposure to nitrate from drinking water and diet was associated with timing of puberty.

METHODS

This cohort study included 15,819 children born from 2000 to 2003 within the Danish National Birth Cohort. Self-reported information on current status of various pubertal milestones was provided every six months by a questionnaire from 11 years of age until 18 years or full maturity, whichever came first. Maternal nitrate intake from diet (mg/day) was derived from a mid-pregnancy food frequency questionnaire and individual level nitrate exposure from drinking water (mg/L) was derived using measurements from Danish public waterworks. Adjusted average differences in months in age at attaining several pubertal milestones as well as the average age difference in age at attaining all the milestones were estimated separately for diet and water using a regression model for interval-censored data. C- and E-vitamin, red meat and processed meat intake were explored as potential effect modifiers in sub-analyses.

RESULTS

No strong associations were observed between prenatal exposure to nitrate and timing of puberty in children. However, sons born of mothers with a nitrate concentration in drinking water at their residential address of > 25 mg/L (half of the World Health Organisation (WHO) guideline value) compared with ≤ 1 mg/L showed a tendency towards earlier age at pubertal development with an average age difference of -1.2 months (95 % confidence interval,-3.0;0.6) for all the pubertal milestones combined.

DISCUSSION

Studies including more highly exposed children are needed before the current WHO drinking water guideline value for nitrate can be considered safe concerning pubertal development.

Periconceptional folic acid supplementation and child asthma: a Right From the Start follow-up study

OBJECTIVE

High maternal folic acid exposure has been studied as a risk factor for child asthma with inconclusive results. Folic acid supplementation that begins before pregnancy may propagate high exposures during pregnancy, particularly in regions with fortified food supplies. We investigated whether folic acid supplementation initiated periconceptionally is associated with childhood asthma in a US cohort.

MATERIALS AND METHODS

We re-contacted mother-child dyads previously enrolled in a prospective pregnancy cohort and included children age 4 to 8 years at follow-up (n = 540). Using first trimester interviews, we assessed whether initial folic acid-containing supplement (FACS) use occurred near/before estimated conception ("periconceptional") or after (during the "first trimester"). Follow-up questionnaires were used to determine if a child ever had an asthma diagnosis ("ever asthma") or asthma diagnosis with prevalent symptoms or medication use ("current asthma"). We examined associations between FACS initiation and asthma outcomes using logistic regression, excluding preterm births and adjusting for child age, sex, maternal race, maternal education, and parental asthma.

RESULTS

Approximately half of women initiated FACS use periconceptionally (49%). Nine percent of children had "ever asthma" and 6% had "current asthma." Periconceptional initiation was associated with elevated odds of ever asthma [adjusted odds ratio (95% Confidence Interval): 1.65 (0.87, 3.14)] and current asthma [1.87 (0.88, 4.01)], relative to first trimester initiation.

CONCLUSION

We observed positive, but imprecisely estimated associations between periconceptional FACS initiation and child asthma. Folic acid prevents birth defects and is recommended. However, larger studies of folic acid dosing and timing, with consideration for childhood asthma, are needed.

Diet and Nutrients Intakes during Infancy and Childhood in Relation to Early Puberty: A Systematic Review and Meta-Analysis

The onset of puberty has become earlier over the decades, and nutrients and diet are related to the timing of puberty onset. Hence, we aimed to investigate the association between diet or nutrients in infancy, childhood and early puberty. PubMed, Embase, and Cochrane library were searched systematically up to 15 April 2022. The pooled relative risks (RRs) or regression coefficients (beta) were estimated using the random-effect model or fixed-effect model according to the heterogeneity between studies. Twenty-two articles on diet or nutrients in childhood and six about breastfeeding in infancy were included. The prolonged breastfeeding duration in infancy could reduce the risk of early menarche (beta 0.31, 95% CI: 0.01, 0.60, p = 0.045). The high intake of yogurt was associated with a 35% reduction in the risk of earlier menarche (RR 0.65, 95% CI: 0.47, 0.89, p = 0.008). Girls with severe food insecurity experienced later menarche (RR 0.81, 95% CI: 0.67, 0.98, p = 0.027). Conversely, due to the high intake of protein, the risk of early menarche increased by 8% (RR 1.08, 95% CI: 1.01, 1.16, p = 0.016). High intake of yogurt, longer duration of breastfeeding, and food insecurity decreased the possibility of earlier menarche, while high intake of protein increased that risk. As a modifiable factor, diet and nutrients in infancy and childhood provide new insights into the future prevention of early puberty.

Secular trends in age at pubertal onset assessed by breast development among Chinese girls: A systematic review

Background

The average age at thelarche has trended downwards worldwide since 1970s; however, the onset age of "precocious puberty", defined as the lower percentiles of thelarche age, has been rarely reported. This systematic review aims to evaluate secular trends in age at thelarche among Chinese girls.

Methods

This systematic review on the age at thelarche during puberty among Chinese girls was conducted via systematic search of both Chinese (Chinese National Knowledge Infrastructure, WanFang Database, and the Chinese Scientific Journals Database) and English (PubMed, Cochrane Library, and Embase) databases. Data were analyzed using the GraphPad Prism v9.0.

Results

A total of 16 studies involving 177,886 Chinese girls were synthesized. The QualSyst scores of these studies were high at an average of 21.25. The timing of Tanner breast stage 2 (B2) occurred earlier over time at the P3, P10, and median ages. Weighted analyses revealed that the overall onset age of B2 tended to be younger at P3, P10, and P25. The age of B2 varied across regions and areas. For example, P3, P10, and median age of B2 in years were younger in southern regions than that in northern regions of China (P3: 5.94 vs. 7.3; P10: 6.6 vs. 7.9; median age: 8.26 vs. 9.5), and median age of B2 in urban areas (8.26 years) was earlier than that in rural areas (10.29 years). In addition, median age of B2 from 12 single-center studies was earlier than that from 4 multicenter studies (8.26 vs. 9.18 years).

Conclusions

The current findings indicated that pubertal breast development age among Chinese girls presented an advanced trend over the past 20 years, which urges the necessity to revisit and redefine "precocious puberty" and provides useful recommendations for clinical practice.

Leptin, ghrelin, nesfatin-1, and orexin-A plasma levels in girls with premature thelarche

PURPOSE

Reducing the mean age of puberty onset in recent years has crucial public health, clinical, and social implications. This study aimed to evaluate the serum levels of appetite-related peptides (leptin, ghrelin, nesfatin-1, and orexin-A) and anthropometric data in girls with premature thelarche (PT).

METHODS

We enrolled 44 girls aged 4-8 years diagnosed with PT and 33 age-matched healthy girls as controls. The demographic data of the girls were obtained using a questionnaire. Anthropometric data were measured and fasting blood samples were collected.

RESULTS

Body weight, height, body mass index (BMI), body fat mass, and basal metabolic rate (BMR) were higher in the PT group than in the control group (p < 0.05). Serum leptin (p < 0.001), nesfatin-1 (p = 0.001), and orxein-A (p < 0.001) levels were significantly higher in the PT group than in healthy controls. However, there were no significant differences in the serum ghrelin levels between the groups (p > 0.05). The results of multivariate logistic regression revealed that serum leptin level (OR (95% CI): 42.0 (10.91, 173.06), p < 0.001), orexin-A (OR (95% CI): 1.14 (1.04, 1.24), p = 0.006), and BMI for age z-score (OR (95% CI): 6.97 (1.47, 33.4), p = 0.014) elevated the risk of incidence of PT at 4-8 girls.

CONCLUSION

These results suggest that in addition to serum leptin levels, serum orexin-A and nesaftin-1 can take part in the initiation of PT. Few studies have investigated the relationship between nesfatin-1 and orexin-A levels and age at onset of puberty; hence, it should be a subject for future studies.

Urinary Biomarkers of Polycyclic Aromatic Hydrocarbons and Timing of Pubertal Development: The California PAH Study

BACKGROUND

Polycyclic aromatic hydrocarbons (PAHs) are endocrine-disrupting chemicals. Few studies have evaluated the association between pubertal development in girls and PAH exposures quantified by urinary biomarkers.

METHODS

We examined associations of urinary PAH metabolites with pubertal development in 358 girls 6-16 years of age from the San Francisco Bay Area enrolled in a prospective cohort from 2011 to 2013 and followed until 2020. Using baseline data, we assessed associations of urinary PAH metabolites with pubertal development stage. In prospective analyses limited to girls who at baseline had not yet started breast (N = 176) or pubic hair (N = 179) development or menstruation (N = 267), we used multivariable Cox proportional hazards regression to assess associations of urinary PAH metabolites with the onset of breast and pubic hair development, menstruation, and pubertal tempo (interval between the onset of breast development and menstruation).

RESULTS

We detected PAH metabolites in >98% of girls. In cross-sectional analyses using baseline data, PAH metabolites were not associated with the pubertal development stage. In prospective analyses, higher concentrations (≥ median) of some PAH metabolites were associated with two-fold higher odds of earlier breast development (2-hydroxy naphthalene, 1-hydroxy phenanthrene, summed hydroxy phenanthrenes) or pubic hair development (1-hydroxy naphthalene) among girls overweight at baseline (body mass index-for-age percentile ≥85) compared with nonoverweight girls with lower metabolites concentrations. PAH metabolites were not associated with age at menarche or pubertal tempo.

CONCLUSIONS

PAH exposures were widespread in our sample. Our results support the hypothesis that, in overweight girls, PAHs impact the timing of pubertal development, an important risk factor for breast cancer.

“It always gets pushed aside:” Qualitative perspectives on puberty and menstruation education in U.S.A. schools

Adolescent girls in the U.S.A. often lack sufficient education on pubertal and menstrual health topics. This educational gap may be growing given the current decline in American elementary and middle schools' delivery of sexual health education. Furthermore, little is known about the actual scope and quality of existing menstruation and puberty education in U.S.A. schools. This paper provides insights into some of the challenges with the delivery of menstruation and puberty education in schools. Qualitative and participatory research methodologies were utilized with Black and Latina girls ages 15–19 and adults working with youth in three U.S.A. cities (Chicago, Los Angeles, and New York City), exploring experiences of menstruation within school and family contexts. Findings revealed tension between school responsibility and family authority in providing menstruation and puberty education in schools, school- and teacher-related delivery challenges, and inadequate and disengaging menstruation and puberty content. Further research is needed on the effectiveness and best practices for providing this education in schools, including improved understanding on student and parent preferences, delivery mediums and the scope of content.

Immune signaling as a node of interaction between systems that sex-specifically develop during puberty and adolescence

Adolescence is pivotal for neural and behavioral development across species. During this period, maturation occurs in several biological systems, the most well-recognized being activation of the hypothalamic-pituitary-gonadal axis marking pubertal onset. Increasing comparative studies of sex differences have enriched our understanding of systems integration during neurodevelopment. In recent years, immune signaling has emerged as a key node of interaction between a variety of biological signaling processes. Herein, we review the age- and sex-specific changes that occur in neural, hypothalamic-pituitary, and microbiome systems during adolescence. We then describe how immune signaling interacts with these systems, and review recent preclinical evidence indicating that immune signaling may play a central role in integrating changes in their typical and atypical development during adolescence. Finally, we discuss the translational relevance of these preclinical studies to human health and wellness.

Trends Toward Earlier Puberty Timing in Girls and Its Likely Mechanisms

This is the first of two installments examining early puberty in girls. The first paper will discuss secular trends in onset of puberty and the possible mechanisms to explain these developments. The potential etiologies examined will include the role of endocrine-disrupting chemicals and obesogens, the impact of body mass index and obesity, genetic and biologic pathways, and the influence of lifestyle behaviors. The second paper of the two-part series will examine the potential health impacts of early puberty on young and adult women and offer suggestions for clinical management and public health prevention.

Examination of pubertal timing and tempo in females and males with autism spectrum disorder compared to typically developing youth

Autism spectrum disorder (ASD) is characterized by impaired social communication and poor adaptation to change; thus, pubertal development may be precarious. Pubertal timing and tempo were measured in 244 youth (7.9% Black, 83.3% White, and 8.7% multiracial) with ASD (N = 140) and typical development (N = 104). Pubertal development was measured using Tanner staging of Genital (G, males), Breast (B, females), and pubic hair (PH) in both sexes at Year 1 (10-13 years), Year 2 (11-14 years), and Year 3 (12-15 years). Nonlinear mixed effects models analyzed interindividual differences in timing and tempo. For both sexes, ASD and higher body mass index were associated with earlier pubertal timing. Males generally exhibited faster tempo than females. Linear regression models did not show associations between pubertal timing and internalizing symptoms at time three. Findings showing advanced pubertal maturation in ASD youth suggest greater risk of psychological, social, and physiological challenges. LAY SUMMARY: Youth with ASD have difficulty in social communication and adaption to change, thus puberty may be a challenging transition. The study examined onset (timing) and progression (tempo) of puberty over three years, using physical exam, in 244 adolescents with and without ASD, enrolled at ages 10-13. ASD youth started puberty earlier, while males generally progressed at a faster pace. Further examination of puberty in ASD should identify impact on social, behavioral, and mental health outcomes.