Prepubertal exposure to polycyclic aromatic hydrocarbons are associated with early pubertal development onset in boys: A longitudinal study

OBJECTIVE

To investigate the effects of polycyclic aromatic hydrocarbons(PAHs) on puberty in boys.

METHODS

695 subjects were selected from four primary schools in Chongqing, China. 675 urine samples from these boys were collected four PAH metabolites: 1-hydroxypyrene, 2-hydroxynaphthoic, 2-hydroxyfluorene, and 9-hydroxyphenanthrene. Pubertal development of 695 boys was assessed at follow-up visits starting in December 2015 and occurring every six months thereafter until now, data used in this article ending in June 2021. A total of 12 follow-up visits were performed. Cox proportional hazards regression models were used to analyze the relationship between PAH metabolite concentrations and indicators of pubertal timing.

RESULTS

The mean age at puberty onset of testicular volume, facial hair, pubic hair, first ejaculation, and axillary hair in boys was 11.66, 12.43, 12.51, 12.72 and 13.70 years, respectively. Cox proportional hazards regression models showed that boys with moderate level of 1-OHPyr exposure was associated with earlier testicular development (hazard ratio [HR] = 1.276, 95% confidence interval [CI]: 1.006-1.619), with moderate level of 2-OHNap were at higher risk of early testicular development (HR = 1.273, 95% CI: 1.002-1.617) and early axillary hair development (HR = 1.355, 95% CI: 1.040-1.764), with moderate level of 2-OHFlu was associated with earlier pubic hair development (HR = 1.256, 95% CI: 1.001-1.577), with high level of 9-OHPhe were at higher risk of early fisrt ejaculation (HR = 1.333, 95% CI: 1.005-1.767) and early facial hair development (HR = 1.393, 95% CI: 1.059-1.831).

CONCLUSION

Prepubertal exposure to PAHs may be associated with earlier pubertal development in boys.

Adolescence is a sensitive period for acrylamide-induced sex hormone disruption: Evidence from NHANES populations and experimental mice

Acrylamide (AA) is widely contaminated in environment and diet. However, the association of AA and sex hormones has rarely been investigated, especially in adolescents, a period of particular susceptibility to sex hormone disruption. In this study, survey-weighted multivariate linear regression models were conducted to determine the association between AA Hb biomarkers [HbAA and glycidamide (HbGA)] and sex hormones [total testosterone (TT) and estradiol (E₂)] in a total of 3268 subjects from National Health and Nutrition Examination Survey (NHANES) 2013-2016 waves. Additionally, adult and pubertal mice were treated with AA to assess the effect of AA on sex hormones and to explore the potential mechanisms. Among all the subjects, significant negative patterns for HbGA and sex hormones were identified only in youths (6-19 years old), with the lowest β being - 0.53 (95% CI: -0.80 to -0.26) for TT in males and - 0.58 (95% CI: -0.93 to -0.23) for E₂ in females. Stratified analysis further revealed significant negative associations between HbGA and sex hormones in adolescents, with the lowest β being - 0.58 (95% CI: -1.02 to -0.14) for TT in males and - 0.54 (95% CI: -1.03 to -0.04) for E₂ in females, while there were no significant differences between children or late adolescents. In mice, the levels of TT and E₂ were dramatically reduced in AA-treated pubertal mice but not in adult mice. AA disturbed the expression of genes in the hypothalamic-pituitary-gonadal (HPG) axis, induced apoptosis of hypothalamus-produced gonadotropin-releasing hormone (GnRH) neurons in the hypothalamus and reduced serum and hypothalamic GnRH levels in pubertal mice. Our study indicates AA could reduce TT and E₂ levels by injuring GnRH neurons and disrupting the HPG axis in puberty, which manifested as severe endocrine disruption on adolescents. Our findings reinforce the idea that adolescence is a vulnerable stage in AA-induced sex hormone disruption.

Timing of Puberty, Pubertal Growth, and Adult Height in Short Children Born Small for Gestational Age Treated With Growth Hormone

CONTEXT

Growth hormone (GH) is used to treat short children born small for gestational age (SGA); however, the effects of treatment on pubertal timing and adult height are rarely studied.

OBJECTIVE

To evaluate adult height and peak height velocity in short GH-treated SGA children.

METHODS

Prospective longitudinal multicenter study. Participants were short children born SGA treated with GH therapy (n = 102). Adult height was reported in 47 children. A reference cohort of Danish children was used. Main outcome measures were adult height, peak height velocity, age at peak height, and pubertal onset. Pubertal onset was converted to SD score (SDS) using Danish reference data.

RESULTS

Gain in height SDS from start of treatment until adult height was significant in both girls (0.94 [0.75; 1.53] SDS, P = .02) and boys (1.57 [1.13; 2.15] SDS, P < .001). No difference in adult height between GH dosage groups was observed. Peak height velocity was lower than a reference cohort for girls (6.5 [5.9; 7.6] cm/year vs 7.9 [7.4; 8.5] cm/year, P < .001) and boys (9.5 [8.4; 10.7] cm/year vs 10.1 [9.7; 10.7] cm/year, P = .002), but no difference in age at peak height velocity was seen. Puberty onset was earlier in SGA boys than a reference cohort (1.06 [-0.03; 1.96] SDS vs 0 SDS, P = .002) but not in girls (0.38 [-0.19; 1.05] SDS vs 0 SDS, P = .18).

CONCLUSION

GH treatment improved adult height. Peak height velocity was reduced, but age at peak height velocity did not differ compared with the reference cohort. SGA boys had an earlier pubertal onset compared with the reference cohort.

Effects on Puberty of Nutrition-Mediated Endocrine Disruptors Employed in Agriculture

Pesticide residues are largely found in daily consumed food because of their extensive use in farming and their long half-life, which prolongs their presence in the environment. Many of these pesticides act as endocrine-disrupting chemicals after pre- or postnatal exposure, significantly affecting, among other things, the time of puberty onset, progression, and completion. In humans, precocious or delayed puberty, and early or delayed sexual maturation, may entail several negative long-term health implications. In this review, we summarize the current evidence on the impact of endocrine-disrupting pesticides upon the timing of the landmarks of female and male puberty in both animals (vaginal opening, first estrus, and balanopreputial separation) and humans (thelarche, menarche, gonadarche). Moreover, we explore the possible mechanisms of action of the reviewed endocrine-disrupting pesticides on the human reproductive system. Access to safe, healthy, and nutritious food is fundamental for the maintenance of health and wellbeing. Eliminating the presence of hazardous chemicals in largely consumed food products may increase their nutritional value and be proven beneficial for overall health. Consequently, understanding the effects of human exposure to hazardous endocrine-disrupting pesticides, and legislating against their circulation, are of major importance for the protection of health in vulnerable populations, such as children and adolescents.

Predictors of reproductive and non-reproductive outcomes of gonadotropin mediated pubertal induction in male patients with congenital hypogonadotropic hypogonadism (CHH)

PURPOSE

To investigate predictors of testicular response and non-reproductive outcomes (height, body proportions) after gonadotropin-induced puberty in congenital hypogonadotropic hypogonadism (CHH).

DESIGN

A retrospective analysis of the puberty induction in CHH male patients, undergoing an off-label administration of combined gonadotropin (FSH and hCG).

METHODS

Clinical and hormonal evaluations before and during gonadotropin stimulation in 19 CHH patients genotyped by Targeted Next Generation Sequencing for CHH genes; 16 patients underwent also semen analysis after gonadotropins.

RESULTS

A lesser increase in testicular volume after 24 months of induction was significantly associated with: (I) cryptorchidism; (II) a positive genetic background; (III) a complete form of CHH. We found no significant correlation with the cumulative dose of hCG administered in 24 months. We found no association with the results of semen analyses, probably due to the low numerosity. Measures of body disproportion (eunuchoid habitus and difference between adult and target height: deltaSDSth), were significantly related to the: (I) age at the beginning of puberty induction; (II) duration of growth during the induction; (III) initial bone age. The duration of growth during induction was associated with previous testosterone priming and to partial forms of CHH.

CONCLUSIONS

This study shows that a strong genetic background and cryptorchidism, as indicators of a complete GnRH deficiency since intrauterine life, are negative predictors of testicular response to gonadotropin stimulation in CHH. Body disproportion is associated with a delay in treatment and duration of growth during the induction, which is apparently inversely related to previous androgenization.

Systematic Review: Puberty suppression with GnRH analogues in adolescents with gender incongruity

CONTEXT

Gender incongruence is defined as disharmony between assigned gender and gender identity. Several interventions are liable in this case including genital affirming surgery among other surgical interventions such as harmonization, and also the use of gonadotropin-releasing hormone agonists (GnRHa) for gonadal shielding. This aids in preventing the development of secondary sexual characteristics related to the genetic sex.

OBJECTIVE

Systematically review the treatment of gender incongruity with GnRHa analogues.

DATA SOURCES

The data source of this research is from Pubmed-Medline and Embase.

STUDY SELECTION

Articles published between 2009 and 2019 which studied transgender adolescents treated with GnRHa were carefully selected.

DATA EXTRACTION

Were extracted: design, sample size, study context, targeted subjects of intervention, outcome measures, and results.

RESULTS

Eleven studies were included. The use of GnRHa seems to be well tolerated by the studied population. When started in pubertal transition, it was associated with a more distinct resemblance to body shape than to the affirmed sex. In addition to preventing the irreversible phenotypic changes that occur in cross-hormonal therapy, the use of GnRHa can equally contribute to the mental health of these adolescents.

LIMITATION

There are few consistent studies on the use of GnRHa for gender incongruence.

CONCLUSION

As the population of transgender children and adolescents grows, they acquire knowledge and greater access to the various forms and stages of treatment for sex reassignment. The medical community needs to be adequately prepared to better serve this population and offer the safest resources available.

Circulating miR-30b levels increase during male puberty

OBJECTIVE

The role of miRNA as endocrine regulators is emerging, and microRNA mir-30b has been reported to repress Mkrn3. However, the expression of miR-30b during male puberty has not been studied.

DESIGN AND METHODS

Circulating relative miR-30b expression was assessed in sera of 26 boys with constitutional delay of growth and puberty (CDGP), treated with low-dose testosterone (T) (n =11) or aromatase inhibitor letrozole (Lz) (n =15) for 6 months and followed up to 12 months (NCT01797718). The associations between the relative expression of miR-30b and hormonal markers of puberty were evaluated.

RESULTS

During the 12 months of the study, circulating miR-30b expression increased 2.4 ± 2.5 (s.d.) fold (P = 0.008) in all boys, but this change did not correlate with corresponding changes in LH, testosterone, inhibin B, FSH, or testicular volume (P = 0.25-0.96). Lz-induced activation of the hypothalamic-pituitary-gonadal (HPG) axis was associated with more variable miR-30b responses at 3 months (P < 0.05), whereas those treated with T exhibited significant changes in relative miR-30b levels in the course the study (P < 0.01-0.05).

CONCLUSIONS

Circulating miR-30b expression in boys with CDGP increases in the course of puberty, and appears to be related to the activity of the HPG axis.

Crocetin Mitigates Irradiation Injury in an In Vitro Model of the Pubertal Testis: Focus on Biological Effects and Molecular Mechanisms

Infertility is a potential side effect of radiotherapy and significantly affects the quality of life for adolescent cancer survivors. Very few studies have addressed in pubertal models the mechanistic events that could be targeted to provide protection from gonadotoxicity and data on potential radioprotective treatments in this peculiar period of life are elusive. In this study, we utilized an in vitro model of the mouse pubertal testis to investigate the efficacy of crocetin to counteract ionizing radiation (IR)-induced injury and potential underlying mechanisms. Present experiments provide evidence that exposure of testis fragments from pubertal mice to 2 Gy X-rays induced extensive structural and cellular damage associated with overexpression of PARP1, PCNA, SOD2 and HuR and decreased levels of SIRT1 and catalase. A twenty-four hr exposure to 50 μM crocetin pre- and post-IR significantly reduced testis injury and modulated the response to DNA damage and oxidative stress. Nevertheless, crocetin treatment did not counteract the radiation-induced changes in the expression of SIRT1, p62 and LC3II. These results increase the knowledge of mechanisms underlying radiation damage in pubertal testis and establish the use of crocetin as a fertoprotective agent against IR deleterious effects in pubertal period.

Short-term outcomes of pubertal suppression in a selected cohort of 12 to 15 year old young people with persistent gender dysphoria in the UK

Background

In adolescents with severe and persistent gender dysphoria (GD), gonadotropin releasing hormone analogues (GnRHa) are used from early/middle puberty with the aim of delaying irreversible and unwanted pubertal body changes. Evidence of outcomes of pubertal suppression in GD is limited.

Methods

We undertook an uncontrolled prospective observational study of GnRHa as monotherapy in 44 12–15 year olds with persistent and severe GD. Prespecified analyses were limited to key outcomes: bone mineral content (BMC) and bone mineral density (BMD); Child Behaviour CheckList (CBCL) total t-score; Youth Self-Report (YSR) total t-score; CBCL and YSR self-harm indices; at 12, 24 and 36 months. Semistructured interviews were conducted on GnRHa.

Results

44 patients had data at 12 months follow-up, 24 at 24 months and 14 at 36 months. All had normal karyotype and endocrinology consistent with birth-registered sex. All achieved suppression of gonadotropins by 6 months. At the end of the study one ceased GnRHa and 43 (98%) elected to start cross-sex hormones.

There was no change from baseline in spine BMD at 12 months nor in hip BMD at 24 and 36 months, but at 24 months lumbar spine BMC and BMD were higher than at baseline (BMC +6.0 (95% CI: 4.0, 7.9); BMD +0.05 (0.03, 0.07)). There were no changes from baseline to 12 or 24 months in CBCL or YSR total t-scores or for CBCL or YSR self-harm indices, nor for CBCL total t-score or self-harm index at 36 months. Most participants reported positive or a mixture of positive and negative life changes on GnRHa. Anticipated adverse events were common.

Conclusions

Overall patient experience of changes on GnRHa treatment was positive. We identified no changes in psychological function. Changes in BMD were consistent with suppression of growth. Larger and longer-term prospective studies using a range of designs are needed to more fully quantify the benefits and harms of pubertal suppression in GD.

Insulin resistant diabetes mellitus in SHORT syndrome: case report and literature review

SHORT syndrome is a rare developmental disorder frequently associated with growth failure and insulin resistant diabetes mellitus (IRDM). Since GH has a diabetogenic effect, GH therapy has been regarded as a contraindication. We observed a Brazilian girl with SHORT syndrome who received GH therapy from 4 6/12 years of age for SGA short stature. GH dosage was increased from 0.23 to 0.36 mg/kg/week, but statural response to GH therapy remained poor. Her blood HbA1c level, though it remained 5.5-6.0% in childhood, began to elevate with puberty and increased to 9.2% at 10 6/12 years of age, despite the discontinuation of GH therapy at 9 11/12 years of age. Laboratory studies indicated antibody-negative IRDM. She was treated with metformin and canagliflozin (a sodium glucose co-transporter 2 (SGLT2) inhibitor), which ameliorated overt diurnal hyperglycemia and mild nocturnal hypoglycemia and reduced her blood HbA1c around 7%. Whole exome sequencing revealed a de novo heterozygous pathogenic variant (c.1945C>T:p.(Arg649Trp)) in PIK3R1 known as the sole causative gene for SHORT syndrome. Subsequent literature review for patients with molecularly confirmed SHORT syndrome revealed the development of IRDM in 10 of 15 GH-untreated patients aged ≥12 years but in none of three GH-treated and six GH-untreated patients aged ≤10 years. These findings imply a critical role of pubertal development and/or advanced age rather than GH therapy in the development of IRDM, and a usefulness of SGLT2 inhibitor in the treatment of IRDM.

Hypothalamo-Pituitary axis and puberty

Puberty is a complex process that culminates in the acquisition of psychophysical maturity and reproductive capacity. This elaborate and fascinating process marks the end of childhood. Behind it lies a complex, genetically mediated neuroendocrine mechanism through which the gonads are activated thanks to the fine balance between central inhibitory and stimulating neuromodulators and hormones with both central and peripheral action. The onset of puberty involves the reactivation of the hypothalamic-pituitary-gonadal (HPG) axis, supported by the initial "kiss" between kisspeptin and the hypothalamic neurons that secrete GnRH (the GnRH "pulse generator"). This pulsatile production of GnRH is followed by a rise in LH and, consequently, in gonadal steroids. The onset of puberty varies naturally between individuals, and especially between males and females, in the latter of whom it is typically earlier. However, pathological variations, namely precocious and delayed puberty, are also possible. This article reviews the scientific literature on the physiological mechanisms of puberty and the main pathophysiological aspects of its onset.

Uterine Development During Induced Puberty in Girls with Turner Syndrome

OBJECTIVE

Most girls and women with Turner syndrome (TS) require estrogen replacement therapy (ERT) to initiate or maintain pubertal development. Most likely, the most fundamental effect of ERT in hypogonadism is the promotion of uterine growth. The optimal ERT model is still being discussed. The present study aimed to assess uterine size in girls with TS in the prepubertal state during and after the induction of puberty and compare it to a healthy population.

METHODS

The analysis encompassed 40 TS girls. The prepubertal and postpubertal control groups contained 20 healthy girls each. All patients with TS were treated with 17-ß estradiol. Uterine imaging was performed with two-dimensional (2D) transabdominal ultrasound. The uterine volume (UV) and fundocervical antero-posterior ratio (FCR) were calculated in patients with TS before the pubertal induction, after 6-12 months of estrogen replacement therapy (ERT), after ≥ 36 months of ERT or ≥ 12 months after menarche.

RESULTS

The average age of TS patients at estrogen introduction and at the last control visit, when the uterus was considered mature, was 12.9 years and 16.1 years, respectively. The UV in patients with TS at the beginning of ERT was 1.55 ± 1.22 cm³ and was not significantly different from the UV in the prepubertal controls. The mature UV in patients with TS was 31.04 ± 11.78 cm³ and was significantly smaller than the UV of the postpubertal controls (45.68 ± 12.51 cm³, p<0.001). The FCR in girls with TS did not differ significantly from that in the prepubertal and postpubertal control groups, respectively. No prognostic factors could be established for the final UV. By the last control visit, thelarche had advanced in most patients to Tanner 4 and 5 (37.5% and 40%, respectively).

CONCLUSIONS

Before the onset of ERT, patients with TS have a uterus similar in size to that in prepubertal healthy girls. Pubertal induction in patients with TS causes a significant increase in the UV that is detectable after 6-12 months of ERT. The mature uterus is smaller in patients with TS than in the age-matched healthy population.

Pubertal induction in adolescents with DMD is associated with high satisfaction, gonadotropin release and increased muscle contractile surface area

BACKGROUND

Pharmacological doses of glucocorticoids (GC) reduce inflammation and preserve muscle function in boys with Duchenne muscular dystrophy (DMD). Delayed puberty and bone fragility are consequences of GC treatment. The aim of this study was to determine the acceptability of a 2-year pubertal induction regimen using 4-weekly testosterone injections and examine changes in physique, bone integrity, muscle pathology (assessed by MRI) and muscle function.

METHODS

Fifteen prepubertal males with DMD, aged 12-17 years and receiving GC, were treated with an incremental testosterone regimen for 2 years. Participants completed a Treatment Satisfaction Questionnaire (TSQM). Data on BMI, bone density, muscle pathology and function were collected at baseline and 2 years later.

RESULTS

Testosterone injections were well tolerated, with high TSQM scores. Baseline BMI z-score was 2.16 (0.90) and 1.64 (1.35) 2 years later. Median testosterone levels were 9.7 nmol/L (IQR: 5.7-11.1) 6-9 months after the last injection with an associated increase in testicular volume. Lumbar spine z-score was 0.22 (s.d. 2.21) at baseline and 0.35 (s.d. 2.21) after 2 years. Upper and lower limb muscle contractile cross-sectional area increased in all participants during the trial (P = 0.05 and P < 0.01, respectively). There was a reduction in T2 relaxation times in most muscle groups with stable upper limb muscle function.

CONCLUSION

Incremental monthly testosterone injections were well tolerated, promoted endogenous testosterone production and had a positive impact on the skeleton and contractile muscle bulk with evidence suggesting a beneficial impact on the underlying disease process.

Short and Long-Term Effects of Growth Hormone in Children and Adolescents With GH Deficiency

The syndrome of impaired GH secretion (GH deficiency) in childhood and adolescence had been identified at the end of the 19^th century. Its non-acquired variant (naGHD) is, at childhood onset, a rare syndrome of multiple etiologies, predominantly characterized by severe and permanent growth failure culminating in short stature. It is still difficult to diagnose GHD and, in particular, to ascertain impaired GH secretion in comparison to levels in normally-growing children. The debate on what constitutes an optimal diagnostic process continues. Treatment of the GH deficit via replacement with cadaveric pituitary human GH (pit-hGH) had first been demonstrated in 1958, and opened an era of therapeutic possibilities, albeit for a limited number of patients. In 1985, the era of recombinant hGH (r-hGH) began: unlimited supply meant that substantial long-term experience could be gained, with greater focus on efficacy, safety and costs. However, even today, the results of current treatment regimes indicate that there is still a substantial fraction of children who do not achieve adult height within the normal range. Renewed evaluation of height outcomes in childhood-onset naGHD is required for a better understanding of the underlying causes, whereby the role of various factors - diagnostics, treatment modalities, mode of treatment evaluation - during the important phases of child growth - infancy, childhood and puberty - are further explored.

Testicular Growth and Pubertal Onset in GH-Deficient Children Treated With Growth Hormone: A Retrospective Study

The prevalence of idiopathic oligozoospermia has been esteemed as high as 75%. An Italian survey has reported bilateral testicular hypotrophy in 14% of final-year high school students. The search for determinants of testicular growth in childhood is important for the primary prevention of spermatogenic failure. Therefore, this retrospective study aimed to evaluate the testicular growth and pubertal onset in deficient children treated recombinant human growth hormone (rhGH). To accomplish this, the clinical charts of 93 patients with GH deficiency (GHD) were carefully reviewed. Their mean age at the time of diagnosis was 11.2 ± 2.4 years. rhGH was administered for 44.0 ± 22.4 months, and the onset of puberty was recorded after a mean of 25.8 ± 22.4 months from the first rhGH administration. As expected, serum insulin-like growth factor 1 (IGF1) levels increased significantly after treatment. Before rhGH therapy, the Tanner stage was I in 59 out of 70 boys (84.3%), II in 8/70 (11.4%), III in 3/70 (4.3%). No one was on stage IV or V. The mean Tanner stage was 1.19 ± 0.51. At the last visit, the Tanner stage was I in 8/72 boys (11.1%), II in 6/72 (8.3%), III in 6/72 (8.3%), IV in 16/72 (22.2%), and V in 36/72 (50.0%). After a mean of 44.0 ± 22.4 months of rhGH treatment, the mean Tanner stage was 4.05 ± 1.30. Patients treated with rhGH showed a significant testicular volume (TV) growth over time, whereas no growth was observed in age-matched but not yet treated patients, even when the age was compatible with a spontaneous start of puberty. The multivariate regression analysis showed that the duration of treatment and the mean rhGH dose significantly predicted the percentage of TV increase. In contrast, age, serum FSH, and IGF1 levels, and final rhGH dose did not impact TV growth over time. In conclusion, these findings suggest that GH may play a role in testicular growth and pubertal onset, despite the descriptive nature of this study. Further properly designed studies are needed to confirm these findings. This knowledge may be useful to implement the diagnostic-therapeutic algorithm in case of a lack of testicular growth in childhood.

Phthalate Exposure, Adolescent Health, and the Need for Primary Prevention

Phthalates, a class of endocrine-disrupting chemicals, are used widely in many consumer products, and exposure can interfere with a range of hormonal functions during early life. These disruptions may alter development during late childhood and adolescence. This article discusses the potential effects of phthalate exposure on adiposity, puberty, and neurodevelopment during late childhood and adolescence. It also highlights studies of behavioral interventions to reduce phthalate exposures and the roles of health care professionals and policy makers in preventing phthalate exposure.

Pubertal development and adult height in patients with congenital hypothyroidism detected by neonatal screening in southern Brazil

Objectives Adequate treatment of congenital hypothyroidism (CH) is required for normal growth and sexual development. To evaluate pubertal development in patients with permanent CH detected by a statewide Neonatal Screening Program of Paraná and, secondly, to evaluate adult height (AH) in a subgroup of patients. Methods Clinical, laboratory, and auxological data obtained from medical records of 174 patients (123 girls). Results Median chronological age (CA) at treatment initiation was 24 days, and mean initial levothyroxine dose was 11.7 ± 1.9 μg/kg/day; mean CA at puberty onset was 11.5 ± 1.3 years (boys) and 9.7 ± 1.2 years (girls); mean CA in girls who underwent menarche (n=81) was 12.1 ± 1.1 years. Thyroid-stimulating hormone (TSH) values above the normal range were observed in 36.4% of the boys and 32.7% of the girls on puberty onset, and in 44.6% around menarche. Among 15 boys and 66 girls who had reached the AH, the median height z-score value was significantly greater than the target height (TH) z-score value in boys (p=0.01) and in girls (p<0.001). Boys with normal TSH values at puberty onset had greater mean AH z-score compared with boys with TSH values above the normal range (p=0.04). Conclusions In this group, pubertal development in girls with CH was not different from that reported in healthy girls in the general Brazilian population. Boys with higher TSH at puberty onset may have an increased risk of not reaching their potential height compared with those with normal TSH during this period. In a subgroup who attained AH, the median AH z-score was greater than the median TH z-score.

Oral contraceptive use, especially during puberty, alters resting state functional connectivity

Millions of women worldwide use oral contraceptives (OCs), often starting during puberty/adolescence. It is, however, unknown how OC use during this critical period of development affects the brain. The objective of the current study was to examine resting state functional connectivity (FC) in the default mode network (DMN), central executive network (CEN), salience network (SN), reward network (RN), and subcortical limbic network of the brain using independent component analysis (ICA) between pubertal- and adult-onset OC users (n = 27) and naturally cycling women (n = 48). It was hypothesized that OC use would result in network-specific increases and decreases in FC and that pubertal-onset OC use would result in differences to the aforementioned networks compared to adult-onset OC use. Pubertal-onset OC use is related to heightened FC in the SN compared to adult-onset OC users. In general, OC use also increases connectivity in the SN, CEN, RN, and subcortical limbic network compared to NC women. No significant differences in connectivity were observed in the DMN between OC users and NC women. These findings provide a mechanistic insight for the altered executive functioning and emotion/reward processing previously seen in OC users, which may then increase their vulnerability to mental health conditions.

Timing and regimen of puberty induction in children with hypogonadism: a survey on the practice in Arab countries

Objectives There are some variations in the practice of puberty induction between different regions; however, data from Arab countries are lacking. We aimed to survey the practice of pediatric endocrinologists in Arab countries on the timing and regimen for puberty induction in girls and boys with hypogonadism. Methods An online questionnaire was emailed to physicians registered in the Arab Society for Paediatric Endocrinology and Diabetes. Results In total, 106 replies from 17 countries were received. In non Turner syndrome (TS) girls, puberty was induced by 49.4% of participants at 12-13 years and by 32.5% at  ≥14 years. Ethinyl estradiol and conjugated estrogen were the most popular preparations used (29.7 and 16.6%, respectively). Of the participants, 60% introduce progesterone either at 2-3 years after starting estrogen or following a significant breakthrough bleeding on estrogen. In girls with TS, 84.2% of participants prescribed estrogen to those aged 11 years and older (51.5% at 11-12 years) and 5.3% prescribed it to those at the prepubertal age. In boys, 57.3% of participants induce at ≥14 years, 80.6% use intramuscular testosterone and 46.5% start with 50 mg/kg/month. Human chorionic gonadotropin is more used in non-Gulf Arab countries (18.2 vs. 2.9%; p 0.036) with a trend of using oral testosterone undecanoate in Gulf states (12.2 vs. 2.0%; p 0.051). Conclusions We describe the approach to puberty induction in boys and girls among pediatric endocrinologists in Arab countries. The observed variation in practice would be useful in developing regional consensus guidelines on puberty induction in children with hypogonadism.

GABAergic input through GABAB receptors is necessary during a perinatal window to shape gene expression of factors critical to reproduction such as Kiss1

Lack of GABAB receptors in GABAB1 knockout mice decreases neonatal ARC kisspeptin 1 (Kiss1) expression in the arcuate nucleus of the hypothalamus (ARC) in females, which show impaired reproduction as adults. Our aim was to selectively impair GABAB signaling during a short postnatal period to evaluate its impact on the reproductive system. Neonatal male and female mice were injected with the GABAB antagonist CGP 55845 (CGP, 1 mg/kg body wt sc) or saline from postnatal day 2 (PND2) to PND6, three times per day (8 AM, 1 PM, and 6 PM). One group was killed on PND6 for collection of blood samples (hormones by radioimmunoassay), brains for gene expression in the anteroventral periventricular nucleus-periventricular nucleus continuum (AVPV/PeN), and ARC micropunches [quantitative PCR (qPCR)] and gonads for qPCR, hormone contents, and histology. A second group of mice was injected with CGP (1 mg/kg body wt sc) or saline from PND2 to PND6, three times per day (8 AM, 1 PM, and 6 PM), and left to grow to adulthood. We measured body weight during development and parameters of sexual differentiation, puberty onset, and estrous cycles. Adult mice were killed, and trunk blood (hormones), brains for qPCR, and gonads for qPCR and hormone contents were obtained. Our most important findings on PND6 include the CGP-induced decrease in ARC Kiss1 and increase in neurokinin B (Tac2) in both sexes; the decrease in AVPV/PeN tyrosine hydroxylase (Th) only in females; the increase in gonad estradiol content in both sexes; and the increase in primordial follicles and decrease in primary and secondary follicles. Neonatally CGP-treated adults showed decreased ARC Kiss1 and ARC gonadotropin-releasing hormone (Gnrh1) and increased ARC glutamic acid decarboxylase 67 (Gad1) only in males; increased ARC GABAB receptor subunit 1 (Gabbr1) in both sexes; and decreased AVPV/PeN Th only in females. We demonstrate that ARC Kiss1 expression is chronically downregulated in males and that the normal sex difference in AVPV/PeN Th expression is abolished. In conclusion, neonatal GABAergic input through GABAB receptors shapes gene expression of factors critical to reproduction.

Safeguarding Female Reproductive Health against Endocrine Disrupting Chemicals-The FREIA Project

Currently available test methods are not well-suited for the identification of chemicals that disturb hormonal processes involved in female reproductive development and function. This renders women's reproductive health at increasing risk globally, which, coupled with increasing incidence rates of reproductive disorders, is of great concern. A woman's reproductive health is largely established during embryonic and fetal development and subsequently matures during puberty. The endocrine system influences development, maturation, and function of the female reproductive system, thereby making appropriate hormone levels imperative for correct functioning of reproductive processes. It is concerning that the effects of human-made chemicals on the endocrine system and female reproductive health are poorly addressed in regulatory chemical safety assessment, partly because adequate test methods are lacking. Our EU-funded project FREIA aims to address this need by increasing understanding of how endocrine disrupting chemicals (EDCs) can impact female reproductive health. We will use this information to provide better test methods that enable fit-for-purpose chemical regulation and then share our knowledge, promote a sustainable society, and improve the reproductive health of women globally.

Kisspeptin and neurokinin B analogs use in gynecological endocrinology: where do we stand?

BACKGROUND

Recent studies have found that kisspeptin/neurokinin B/dynorphin neurons (KNDy neurons) in the infundibular nucleus play a crucial role in the reproductive axis. Analogs, both agonists and antagonists, of kisspeptin and neurokinin B (NKB) are particularly important in explaining the physiological role of KNDy in the reproductive axis in animals. The use of kisspeptin and NKB analogs has helped elucidate the regulators of the hypothalamic reproductive axis.

PURPOSE

This review describes therapeutic uses of Kiss-1 and NKB agonists, most obviously the use of kisspeptin agonists in the treatment for infertility and the induction of ovulation. Kisspeptin antagonists may have potential clinical applications in patients suffering from diseases associated with enhanced LH pulse frequency, such as polycystic ovary syndrome or menopause. The inhibition of pubertal development using Kiss antagonists may be used as a therapeutic option in precocious puberty. Kisspeptin antagonists have been found capable of inhibiting ovulation and have been proposed as novel contraceptives. Hypothalamic amenorrhea and delayed puberty are conditions in which normalization of LH secretion may potentially be achieved by treatment with both kisspeptin and NKB agonists. NKB antagonists are used to treat vasomotor symptoms in postmenopausal women, providing rapid relief of symptoms while supplanting the need for exogenous estrogen exposure.

CONCLUSIONS

There is a wide spectrum of therapeutic uses of Kiss-1 and NKB agonists, including the management of infertility, treatment for PCOS, functional hypothalamic amenorrhea or postmenopausal vasomotor symptoms, as well as contraceptive issues. Nevertheless, further research is needed before kisspeptin and NKB analogs are fully incorporated in clinical practice.

Effect of Dosage of 17ß-Estradiol on Uterine Growth in Turner Syndrome-A Randomized Controlled Clinical Pilot Trial

CONTEXT

Most Turner syndrome (TS) girls need exogenous estrogen treatment to induce puberty and normal uterine growth. After puberty, the optimal estrogen treatment protocol has not been determined.

OBJECTIVE

To compare 2 doses of oral 17ß-estradiol on uterine size.

DESIGN

A double-blind, 5-year randomized controlled clinical trial.

SETTING

Ambulatory care.

PARTICIPANTS

Twenty young TS women (19.2 ± 2.5 years, range 16.0-24.9) participated. Sixteen patients completed the study. No patients withdrew due to adverse effects.

INTERVENTION

The lower dose (LD) group took 2 mg 17ß-estradiol/d orally and placebo. The higher dose (HD) group took 4 mg 17ß-estradiol/d orally.

MAIN OUTCOME MEASURE(S)

Uterine volume evaluated by transabdominal ultrasound yearly.

RESULTS

Uterine size increased significantly more in the HD group compared with the LD group (P = 0.038), with a gain in uterine volume within the first 3 years of treatment of 19.6 mL (95% confidence interval [CI] = 4.0-19.0) in the HD group compared with 11.5 mL (95% CI = 11.2-27.9) in the LD group. The difference in 3-year gain was 8.1 mL (95% CI = 0.7-15.9). At the last visit, there were no significant differences in uterine volume between the groups.

CONCLUSION

HD oral 17ß-estradiol induces a steeper increase in uterine volume within the first years of treatment compared with the LD. However, the uterine growth potential seems to be the same in most young TS women making the duration of treatment equally significant as estrogen dose, although a few TS women did not experience sufficient uterine growth on 2 mg of estradiol.

CLINICALTRIALS.GOV

NCT00134745Abbreviations: BMI, body mass index; BSA, body surface area; DHEAS, dihydroepiandrosteronesulfate; HD, higher dose; HRT, hormone replacement therapy; LD, lower dose; TS, Turner syndrome; US, ultrasound.

Update on methods to enhance growth

PURPOSE OF REVIEW

To discuss treatments used to enhance growth in pediatric patients with short stature.

RECENT FINDINGS

New data confirm the known efficacy of recombinant human growth hormone (rhGH) in growth hormone deficiency (GHD) and idiopathic short stature. The latest data from the Safety and Appropriateness of Growth hormone Treatment in Europe cohort did not indicate a long-term risk of malignancy in those treated for isolated GHD, but possibly increased risk in those with other diagnoses. Recombinant human insulin-like growth factor 1 is effective in treating patients with pregnancy-associated plasma protein A2 deficiency. Gonadotropin-releasing hormone agonists or aromatase inhibitor treatment to delay puberty remains controversial. They are more likely to augment adult height if combined with rhGH treatment in children already receiving rhGH. Preliminary data indicate that recombinant C-type natriuretic peptide (CNP) is safe in children and increases growth velocity upon 42 months of treatment in achondroplasia.

SUMMARY

Recent data confirms previous data on rhGH efficacy and safety. Therapies to delay growth plate closure have greatest efficacy to augment height if combined with GH in select diagnoses. Recombinant CNP holds promise as a medical treatment for short stature associated with achondroplasia.

The effect of GnRH antagonist cetrorelix on Wnt signaling members in pubertal and adult mouse ovaries

Wide application of gonadotropin-releasing hormone (GnRH) agonists and antagonists for clinical purposes determines their effects on ovarian signaling pathways. Our study aimed to determine the localization, expression levels of Wnt signaling members in the pubertal and adult mouse ovary and the impact of GnRH antagonist cetrorelix on these signaling members. 0.5 mg/kg of cetrorelix was injected to 3-and 6-week-old mice for 2 weeks. At the end of injection, ovaries from 5 (5Ce)- to 8-week (8Ce)-old mice were embedded in paraffin for immunohistochemistry and homogenized for western blot to compare with control (5C-8C) and sham groups (5S-8S). WNT2 and WNT4 showed higher expression in thecal and stromal cells in adult mouse ovaries and only WNT4 expression was affected by cetrorelix. FZD1 was localized mainly in oocytes of pubertal ovaries and granulosa cells and oocytes of adult ovaries. FZD1 was reduced by cetrorelix in pubertal ovaries. FZD4 was abundantly localized in thecal and stromal cells of all groups and protein level was not affected by cetrorelix. LRP-6 was expressed mainly in oocytes and stromal cells of pubertal, oocytes of adult ovaries and its expression was reduced by cetrorelix in adult ovaries. CTNNB1 intensity in granulosa cells was the lowest in pubertal and the highest in adult ovaries and its expression was decreased by cetrorelix in adult ovaries. Cetrorelix affected the expression of specific members of the Wnt signaling depending on the developmental stage of mice, pointing out its possible interaction with gonadotropins during pubertal and adult stages.

Transition memories: experiences of trans adult women with hormone therapy and their beliefs on the usage of hormone blockers to suppress puberty

PURPOSE

In recent years, an increasing number of specialized gender clinics have been prescribing gonadotropin-releasing hormone (GnRH) analogs to adolescents diagnosed with gender dysphoria (GD) to suppress puberty. This paper presents qualitative research on the hormone therapy (HT) experiences of older trans-people and their views on puberty suppression. The main aim of this research was to explore the psychological aspects of hormonal treatments for gender non-conforming adults, including the controversial use of puberty suppression treatments.

METHODS

Using a semi-structured interview format, ten adult trans-women were interviewed (mean age: 37.4) to explore their personal histories regarding GD onset and development, their HT experiences, and their views on the use of GnRH analogs to suppress puberty in trans-children and adolescents.

RESULTS

the interview transcripts were analyzed using the consensual qualitative research method from which several themes emerged: the onset of GD, childhood experiences, experiences with puberty and HT, views on the puberty suspension procedure, and the effects of this suspension on gender identity and sexuality.

CONCLUSIONS

The interviews showed that overall, the participants valued the new treatment protocol due to the opportunity to prevent the severe body dysphoria and social phobia trans-people experience with puberty. It seems that the risk of social isolation and psychological suffering is increased by the general lack of acceptance and stigma toward trans-identities in the Italian society. However, during gender transitions, they highlight the need to focus more on internal and psychological aspects, rather than over-emphasize physical appearance. This study gives a voice to an under-represented group regarding the use of GnRH analogs to suppress puberty in trans-individuals, and collected firsthand insights on this controversial treatment and its recommendations in professional international guidelines.

Effects of pre- and post-pubertal dihydrotestosterone treatment on penile length in 5α-reductase type 2 deficiency

Steroid 5α-reductase type 2 deficiency (5αRD2) is a congenital disorder of sex development caused by impairment of conversion from testosterone (T) to 5α-dihydrotestosterone (DHT). DHT deficiency leads to various degrees of undervirilized external genitalia including micropenis, primarily correlated with mutations of the SRD5A2 gene that encodes 5α-reductase type 2. Four Japanese boys with isolated micropenis were diagnosed as 5αRD2 by elevated ratios of serum T/DHT, and decreased ratios of urinary 5α/5β-reduced steroid metabolites. Genetic analyses for SRD5A2 identified that the four patients shared a hypomorphic mutation R227Q that has a residual activity related to the mild-form of 5αRD2. For prepubertal micropenis, DHT was transdermally applied to the four patients at the ages of 4-11 year, increasing a median of stretched penile lengths (SPLs) from 2.6 cm (-2.5 SD) to 4.4 cm (-0.2 SD). Nevertheless, the post-pubertal penile growth was apparently retarded, despite normal levels of T secreted from well-developed testes. The second course of DHT treatment underwent at ages of 12-18 year, but unable to normalize SPLs at a range of 6.0 to 7.0 cm (-3.4 to -2.4 SD). The prostate volumes of two patients were variable at 8.1 and 21 cm³, and a sperm cell count of one patient was normal as young adult. DHT treatment contributes to development of the penis and prostate, which are favorable for the potential fertility of 5αRD2 adults. Meanwhile, the retarded penile growth and a risk of prostate overgrowth may complicate the post-pubertal management with DHT for 5αRD2 males.

4-Bromodiphenyl Ether Causes Adrenal Gland Dysfunction in Rats during Puberty

Polybrominated diphenyl ethers (PBDEs) are a group of flame retardants with two or more bromines attached. They are endocrine disruptors. PBDEs photodegrade into 4-bromodiphenyl ether (BDE3). Whether BDE3 impairs adrenal cortical cell function during postnatal development still remains unknown. The aim of the current study was to investigate the influence of BDE3 on adrenal cortical cell function. Sprague-Dawley rats (35 days of age, male) were orally administered with BDE3 (0, 50, 100, and 200 mg/kg/day body weight) for 21 days. BDE3 significantly increased serum aldosterone and corticosterone levels at 200 mg/kg without affecting adrenocorticotropic hormone level. Further study showed that BDE3 up-regulated Cyp11b1 at 100 and 200 mg/kg and Scarb1, Star, Cyp11b2, Cyp21, and Nr5a1 mRNA levels in the 200 mg/kg group. BDE3 also decreased the phosphorylation of AMP-activated protein kinase (AMPK) at 200 mg/kg and increased PGC-1α and phosphorylated cyclic AMP-responsive element-binding protein (CREB)/CREB at 200 mg/kg. Taken together, these findings demonstrate that BDE3 stimulates adrenal cell function likely through decreasing phosphorylation of AMPK and increasing phosphorylation of CREB.

Near Adult Height in Girls with Turner Syndrome Treated with Growth Hormone Following Either Induced or Spontaneous Puberty

OBJECTIVE

To understand whether spontaneous vs induced puberty and the type and route of estrogen influence the height of girls with Turner syndrome on growth hormone (GH).

STUDY DESIGN

Search of an international database of children treated with GH revealed 772 girls with Turner syndrome followed from GH initiation to near adult height. Data from girls with sustained spontaneous puberty (n = 145) were compared with those requiring estrogens for induction or maintenance of puberty (n = 627).

RESULTS

At GH start, mean age (7.5 vs 7.9 years), weight (-1.7 vs -1.7 SDS), and body mass index (0.2 SDS vs 0.1 SDS) were similar for girls with spontaneous puberty and with induced puberty. Although those girls with spontaneous puberty were shorter than those with induced puberty, when midparental height was taken into consideration, starting heights in both groups averaged -2.8 SDS. Both groups received approximately 0.3 mg/kg/week of GH. Girls with spontaneous puberty initiated puberty and reached near adult height earlier than girls with induced puberty (12.6 ± 1.8 years vs 13.4 ± 1.4 years and 16.0 ± 1.3 years vs 16.9 ± 1.4 years, respectively). Although girls with spontaneous puberty grew more in the first year of GH therapy and between the onset of puberty and near adult height (11.0 cm vs 9.3 cm), height SDS at near adult height and the length of time in puberty before reaching near adult height were comparable. A 45,X karyotype was detected in 22.1% of girls with spontaneous puberty and in 58.4% of girls with induced puberty. Patients receiving transdermal estrogens did not grow better than those on oral estrogens. Adverse event reporting was comparable between groups.

CONCLUSIONS

Girls with Turner syndrome with spontaneous puberty tended to grow better in response to GH than girls with induced puberty, but not enough to produce a difference in height SDS at near adult height.

Phthalate exposure and female reproductive and developmental outcomes: a systematic review of the human epidemiological evidence

OBJECTIVE

We performed a systematic review of the epidemiology literature to identify the female reproductive and developmental effects associated with phthalate exposure.

DATA SOURCES AND STUDY ELIGIBILITY CRITERIA

Six phthalates were included in the review: di(2-ethylhexyl) phthalate (DEHP), diisononyl phthalate (DINP), dibutyl phthalate (DBP), diisobutyl phthalate (DIBP), butyl benzyl phthalate (BBP), and diethyl phthalate (DEP). The initial literature search (of PubMed, Web of Science, and Toxline) included all studies of female reproductive and developmental effects in humans, and outcomes were selected for full systematic review based on data availability.

STUDY EVALUATION AND SYNTHESIS METHODS

For each outcome, studies were evaluated using criteria defined a priori for risk of bias and sensitivity by two reviewers using a domain-based approach. Evidence was synthesized by outcome and phthalate and strength of evidence was summarized using a structured framework.

RESULTS

The primary outcomes reviewed here are (number of included/excluded studies in parentheses): pubertal development (5/13), time to pregnancy (3/4), preterm birth (8/12), and spontaneous abortion (5/0). Among these outcomes, preterm birth had moderate evidence of a positive association with phthalate exposure (specifically DEHP, DBP, and DEP). Exposure levels for BBP, DIBP, and DINP were generally lower than for the phthalates with an observed effect, which may partially explain the difference due to lower sensitivity. Other phthalate/outcome combinations were considered to have slight or indeterminate evidence of an association.

CONCLUSIONS AND IMPLICATIONS OF KEY FINDINGS

Overall, these results support that some phthalates may be associated with higher odds of preterm birth in humans, though there is some remaining inconsistency. More evidence is needed on the mechanism and relevant exposure window for this association. The views expressed are those of the authors and do not necessarily represent the views or policies of the U.S. EPA.

Reproductive disorders in female rats after prenatal exposure to sodium arsenite

Arsenic is a metalloid widely found in the environment in organic and inorganic forms. Exposure to inorganic arsenic forms via drinking water has been associated with an increased incidence of negative health effects, including reproductive disorders and dysfunction of the endocrine system. However, the impact of arsenic exposure on female reproductive development is still unclear. Therefore, in the present study, we evaluated the effects of prenatal exposure to arsenic on the initial sexual development and puberty onset, and in the morphology of the female reproductive organs, estrous cycle regularity and fertility parameters during adulthood. To do that, pregnant female Wistar rats were exposed to 10 mg/L sodium arsenite via drinking water from gestational day (GD) 1 until GD 21 and the female offspring was evaluated in different postnatal days. Our results showed that prenatal arsenic exposure induced a decrease of litter weight and morphological masculinization in females at postnatal day 1. Moreover, these females had a delay in the age of puberty onset and alteration in estrous cycle number and length. During adulthood, females from the sodium arsenite group showed an increase in endometrium, myometrium and perimetrium areas, and an imbalance in uterine antioxidant enzyme activity. These animals also presented an increase in post-implantation loss and reabsorption number, leading to reduced viable fetus number. In conclusion, prenatal arsenic exposure in rats was able to promote female masculinization, alter sexual development and impair reproductive performance.

The Beneficial Effect of Combined GH/GnRHa Therapy in Increasing Adult Height Outcome in Children With ISS

CONTEXT

Management of GH-treated children with idiopathic short stature (ISS) with early puberty and adolescents in midpuberty at initiation of treatment is challenging.

OBJECTIVE

To assess the effect of combined GH/GnRHa therapy during puberty on achieved adult height (AHt) in these children with ISS and to determine whether outcome depended on sex and pubertal status at initiation of GH therapy.

DESIGN

Retrospective, single-center observational study from 2003-2018.

SETTING

Tertiary endocrine center.

PATIENTS

One hundred ninety-two GH-treated children with ISS; 58 of 192 were treated by GH/GnRHa during puberty; 31 of 58 were prepubertal (19 girls) and 27 of 58 pubertal (19 girls) at initiation of GH.

MAIN OUTCOME MEASURES

AHt, gain-in-height standard deviation score (SDS), AHt vs predicted adult height (PAHt), AHt vs target height (THt).

RESULTS

Most boys and girls attained AHt SDS within the normal range (-0.73 ± 0.60 and -0.85 ± 0.65, respectively). Treatment modality, pubertal status, and sex were tested for their joint effect on growth outcome measures. Combined GH/GnRHa therapy increased AHt vs PAHt (P < 0.001) and AHt vs THt (P = 0.035). Prepubertal status at onset of GH treatment increased AHt (P = 0.049), gain-in-height SDS (P < 0.001), AHt vs PAHt (P < 0.001), and AHt vs THt (P = 0.042). Female sex increased AHt vs PAHt (P < 0.001).

CONCLUSIONS

Our study demonstrated a beneficial effect of combined GH/GnRHa therapy in increasing AHt outcome in children with ISS with early/normal puberty and in adolescents naïve to GH treatment who are in midpuberty at initiation of therapy. This effect was more pronounced in the prepubertal group and in girls. Prospective randomized controlled trials are needed to assess whether GnRHa can increase AHt in GH-treated children with ISS.

Hormone Therapy in Children and Adolescents

For children and adolescents with gender dysphoria, an interdisciplinary care team is essential for proper diagnosis and appropriate treatment. For children who present with gender dysphoria, once puberty begins, they can be treated with gonadotropin-releasing hormone analogs to stop pubertal progression. This allows for further gender exploration, relief of dysphoria, and better cosmetic outcomes by avoiding the physical changes associated with puberty of the gender assigned at birth. After pubertal suppression, the individual may opt to proceed with puberty or start treatment with gender-affirming hormones.

Endocrine disrupters and possible contribution to pubertal changes

The onset of puberty strongly depends on organizational processes taking place during the fetal and early postnatal life. Therefore, exposure to environmental pollutants such as Endocrine disrupting chemicals (EDCs) during critical periods of development can result in delayed/advanced puberty and long-term reproductive consequences. Human evidence of altered pubertal timing after exposure to endocrine disrupting chemicals is equivocal. However, the age distribution of pubertal signs points to a skewed distribution towards earliness for initial pubertal stages and towards lateness for final pubertal stages. Such distortion of distribution is a recent phenomenon and suggests environmental influences including the possible role of nutrition, stress and endocrine disruptors. Rodent and ovine studies indicate a role of fetal and neonatal exposure to EDCs, along the concept of early origin of health and disease. Such effects involve neuroendocrine mechanisms at the level of the hypothalamus where homeostasis of reproduction is programmed and regulated but also peripheral effects at the level of the gonads or the mammary gland.

Blood lead levels and timing of male sexual maturity: A longitudinal study of Russian boys

BACKGROUND

Higher blood lead levels (BLLs) have been linked to neurologic deficits and impaired growth, but few studies have evaluated their association with timing of sexual maturity or pubertal progression in boys.

METHODS

In a longitudinal cohort of Russian boys enrolled at age 8-9 and followed to adulthood, BLLs were measured at study entry, and pubertal staging (genitalia and pubic hair) and testicular volume (TV) measurements were obtained annually. We used interval-censored regression models to estimate differences between boys with higher BLL (≥5 μg/dL) and lower BLL in mean ages at sexual maturity (genitalia stage 5, pubic hair stage 5, or TV ≥ 20 mL) and duration of pubertal progression (onset to maturity), adjusting for potential confounders. Mediation analyses were conducted to quantify the percent of lead's effect attributable to its association with reduced somatic growth.

RESULTS

Among 481 evaluable boys, 28% had BLL ≥ 5 μg/dL. Adjusted mean ages at sexual maturity were 14.7 years for genitalia, 16.1 for pubic hair, and 13.9 for TV. In adjusted models, boys with BLLs ≥5 μg/dL had later maturity than those with lower levels by 4-5 months depending on pubertal indicator. In mediation analyses, height and body mass index at age 11 accounted for 40-71% of the shift in age at maturity for boys with higher compared to lower BLLs. Higher BLLs were not associated with pace of pubertal progression.

CONCLUSIONS

Higher lead levels were associated with later attainment of sexual maturity in males, but not with the duration of pubertal progression. A high proportion of the delay in sexual maturity for boys with higher as compared to lower BLL was shown to be attributable to mediating effects of BLL on reduced growth.

Early lead exposure and pubertal development in a Mexico City population

BACKGROUND

Previous studies have examined the association between blood lead levels and pubertal timing in adolescent girls; however, the evidence is lacking on the role of lead exposure during sensitive developmental periods on sexual maturation.

OBJECTIVES

To examine the association of prenatal and early childhood lead exposure with pubertal stages among 264 boys and 283 girls aged 9.8-18.0 years in Mexico City.

METHODS

We measured maternal bone lead (a proxy for cumulative fetal exposure to lead from maternal bone stores mobilized during pregnancy) at 1 month postpartum. Blood lead was measured annually from 1 to 4 years. Pubertal stage was assessed by a pediatrician. We examined the association between lead and pubertal stages of breast, pubic hair and genitalia using ordinal regression. Age at menarche was evaluated using Cox proportional-hazard models.

RESULTS

Multivariate models showed that maternal patella lead and early childhood blood lead were inversely associated with breast growth (patella OR = 0.72, 95% CI: 0.51-1.00; blood OR = 0.70, 95% CI: 0.53-0.93) in girls. Girls with maternal patella lead in the 3rd tertile and child blood lead in the 2nd tertile had a later age at menarche compared with girls in the 1st tertile (patella HR = 0.60, 95% CI: 0.41-0.88; blood HR = 0.65, 95% CI 0.46-0.91). Additionally, early childhood blood lead was negatively associated with pubic hair growth (OR = 0.68, 95% CI: 0.51-0.90) in girls. No associations were found in boys.

CONCLUSIONS

These data suggest that higher prenatal and early childhood exposure to lead may be associated with delayed pubertal development in girls but not boys. Our findings are consistent with previous analyses and reinforce the reproductive effects of lead for girls.

Unraveling the Paradoxical Action of Androgens on Muscle Stem Cells

Androgens act in almost all tissues throughout the lifetime and have important roles in skeletal muscles. The levels of androgens increase during puberty and remain sustained at high levels in adulthood. Because androgens have an anabolic effect on skeletal muscles and muscle stem cells, these increased levels of androgens after puberty should lead to spontaneous muscle hypertrophy and hyperplasia in adulthood. However, the maintenance of muscle volume, myonuclei number per myofiber, and quiescent state of satellite cells in adulthood despite the high levels of androgens produces paradoxical outcomes. Our recent study revealed that the physiological increase of androgens at puberty initiates the transition of muscle stem cells from proliferation to quiescence by the androgen-Mindbomb1-Notch signaling axis. This newly discovered androgen action on skeletal muscles underscores the physiological importance of androgens on muscle homeostasis throughout life. This review will provide an overview of the new androgen action on skeletal muscles and discuss the paradoxical effects of androgens suggested in previous studies.

Exposure to Perfluoroalkyl Substances during Fetal Life and Pubertal Development in Boys and Girls from the Danish National Birth Cohort

BACKGROUND

It remains unsettled whether prenatal exposure to perfluoroalkyl substances (PFASs) affects human reproductive health through potential endocrine disruption.

OBJECTIVES

We aimed to explore the associations between prenatal exposure to several PFASs and various aspects of pubertal development in boys and girls.

METHODS

We studied two samples ([Formula: see text] and 445) from the Puberty Cohort, nested within the Danish National Birth Cohort (DNBC), measuring PFAS in maternal plasma from early gestation. Data on pubertal development were collected biannually from the age of 11 y until full maturation, using web-based questionnaires. Outcomes were age at menarche, voice break, first ejaculation, and Tanner stages 2 to 5 for pubic hair, breast, genital development, and a combined puberty indicator. A regression model for censored data was used to estimate mean difference (months) in age at achieving the pubertal outcomes across tertiles of PFAS concentrations and with a doubling of PFAS concentrations (continuous). For perfluorooctanoic acid (PFOA) and perfluorooctanesulfonic acid (PFOS), a meta-analysis was used to provide a weighted average of the point estimates from samples 1 and 2.

RESULTS

Overall, prenatal exposure to PFOS, perfluorohexane sulfonate (PFHxS), perfluoroheptane sulfonate (PFHpS), perfluorononanoic acid (PFNA), and perfluorodecanoic acid (PDFA) (girls) and PFHxS and PFHpS (boys) was associated with lower mean age at puberty marker onset. PFDA and PFNA exposure was associated with higher mean age at onset of puberty in boys. Nonmonotonic associations in girls (PFOS, PFHpS, PFDA) and boys (PFDA, PFNA) were observed, showing larger mean age differences for the combined puberty indicator in the middle tertile [girls: PFOS: [Formula: see text] mo, 95% confidence interval (CI): [Formula: see text], [Formula: see text]; PFHpS: [Formula: see text] mo, 95% CI: [Formula: see text], 1.85; PFDA: [Formula: see text] mo, 95% CI: [Formula: see text], 1.83; and boys: PFNA: 4.45 mo, 95% CI: [Formula: see text], 10.21; PFDA: 4.59 mo, 95% CI: [Formula: see text], 10.11] than in the highest tertile with the lowest as reference.

CONCLUSIONS

Our population-based cohort study suggests sex-specific associations of altered pubertal development with prenatal exposure to PFASs. These findings are novel, and replication is needed. https://doi.org/10.1289/EHP3567.

GnRH analog is ineffective in increasing adult height in girls with puberty onset after 7 years of age: a systematic review and meta-analysis

Objective We assessed the effectiveness of puberty blockade with a gonadotropin-releasing hormone (GnRH) analog in increasing adult height (AH) in girls with puberty onset between 7 and 10 years of age. Methods We performed a systematic review and included controlled studies in which girls with early puberty (EP) were assigned to the GnRH analog or no treatment groups. The primary outcome analyzed was AH. Search strategies were applied to the MEDLINE, EMBASE, LILACS and CENTRAL databases. Results We identified 1514 references, and six studies fulfilled our eligibility criteria. Two studies were randomized and four were not randomized. At the baseline of each trial, height, chronological age, bone age, predicted AH (PAH) and target height (TH) were equal between the groups. All studies used intramuscular triptorelin every 28 days in the intervention groups. The mean duration of the therapy was 2 years. Meta-analysis of AH among the six studies (comprising 332 girls) showed no significant difference between the groups (mean difference = 0.50 cm, 95% confidence interval = -0.72 to 1.73 cm, I 2 = 0%). In a sub-group analysis based on PAH (<155 cm and 155 cm and equal to TH), there was no difference in average AH between the groups. The quality of evidence according to the Grading of Recommendations Assessment, Development and Evaluation approach was low. Conclusion We found no evidence from controlled experimental and observational studies that compared with no treatment, the use of GnRH analogs improved AH in girls with EP.

The Dynamic Trends of Urinary LH and FSH Assayed by ICMA During Triptorelin Stimulation Tests in Girls - a Pilot Study

BACKGROUND

Gonadotropin-releasing hormone stimulation test is a gold standard for evaluating the function of the hypothalamic-pituitary-gonadal axis (HPGA) in children. These tests are usually uncomfortable because of multi-venipunctures. A urine specimen is a good alternative because it is noninvasive and convenient. More studies have shown the correlation between sera and urine LH and FSH levels under different physiological and pathological conditions.

METHODS

The study investigated the dynamic trends of urine LH (uLH) and FSH (uFSH) assayed by immunochemiluminometric assays (ICMA) during triptorelin stimulation tests in girls. The triptorelin stimulation tests were performed in 52 girls with disorders of puberty. The time 0 hour was regarded as the start time of the test (8:30 am). The day before the tests, urine samples were collected at 12 hours diurnal (-24 hours ~ -12 hours) and nocturnal (-12 hours ~ 0 hour) time points. On the day of the testing, the first 12 hours (0 hour ~ 12 hours), the second 12 hours (12 hours ~ 24 hours), the third 12 hours (24 hours ~ 36 hours), the fourth 12 hours (36 hours ~ 48 hours), the third and fourth overnight urine samples were also collected. The LH and FSH levels were assayed by ICMA, and uLH and uFSH were corrected for creatinine (Cr).

RESULTS

The HPGA in 41 girls was activated but it was nonactivated in 11 girls. In girls with HPGA activated, uLH/Cr or uFSH/Cr was significantly elevated within 24 hours, and gradually dropped to baseline after 48 hours. When HPGA was nonactivated in girls, there were the same dynamic trends but much lower amplitude of uLH/Cr or uFSH/Cr, which dropped to baseline after 24 hours.

CONCLUSIONS

The stimulated uLH and uFSH assayed by ICMA are valuable for evaluating the function of HPGA in girls, and the valuable time window is within 24 hours.

Oxandrolone Treatment Results in an Increased Risk of Gonadarche in Prepubertal Boys With Klinefelter Syndrome

CONTEXT

Klinefelter syndrome (KS) is a common genetic condition in which males have an extra X chromosome. KS is associated with testosterone deficiency, neurodevelopmental delays, and cardiometabolic disorders. There has been recent interest in prepubertal androgen treatment; however, the effects on puberty and gonadal function are unknown.

OBJECTIVE

To compare onset of puberty and testicular function in prepubertal boys treated with 2 years of oxandrolone (Ox) vs placebo (Pl).

DESIGN

Double-blind, randomized, controlled trial.

SETTING

Single tertiary care referral center.

PARTICIPANTS

Eighty prepubertal boys with KS; mean age: 8.0 ± 2.2 years (range: 4 to 12).

INTERVENTIONS

Ox 0.05 mg/kg vs identical-appearing Pl capsule given for 2 years.

OUTCOME MEASURES

Onset of gonadarche (testicular volume ≥4 mL) and onset of pubarche (Tanner 2 pubic hair); change in testicular hormone concentrations.

RESULTS

Ox-treated group had 20.5 times higher odds of reaching gonadarche (OR 95% CI: 6.5, 77.8) and 28.1 times higher odds of reaching pubarche (OR 95% CI: 8.8, 110.4) during the 2-year study period after adjusting for baseline age. Gonadarche and pubarche both occurred at a younger age in the Ox group (gonadarche: 9.8 ± 1.5 vs 12.1 ± 1.0 years, P < 0.001; pubarche: 10.2 ± 1.1 vs 11.6 ± 1.3 years, P = 0.02). Serum concentrations of testicular hormones and gonadotropins were not different between groups.

CONCLUSIONS

Two years of Ox treatment in prepubertal boys with KS results in an increased risk of early gonadarche, on average 2 years earlier than in Pl-treated boys. Ox did not affect serum concentrations of testicular hormones.

[Assessment of the suppression of puberty in children with gender identity problems]

The objective of this article is to reflect on the opportunity and risk of the proposed treatments to address gender identity problems in that sector of the population. In most of the protocols for the care of minors with gender identity problems, the abolition of puberty is proposed as a method of choice. This technique consists in the administration of reversible agonists of GnRH to provoke a suppression of the hormonal expression of the minor and, thus, the development of the sexual characters of their gender. The opportunity or adequacy of the systematic use of reversible GnRH agonists may be questioned for several reasons. The first, because the diagnosis of transsexualism in minors carries a great complexity and difficulty, so there is a wide margin of error. The second, because the suppression of puberty has direct consequences in the development of the child. Thirdly, because the aforementioned treatments have some risks and side effects in minors, some of them not studied and unknown, which, without a doubt, should be weighted. Finally, because the drugs used are neither designed nor experienced, for the care of minors with gender identity problems. Therefore, they are used without being approved by the regulatory agencies of the medicinal product for that purpose. These issues need to be addressed and also transmitted in the information provided to the stakeholders.

Perinatal exposure to a glyphosate-based herbicide impairs female reproductive outcomes and induces second-generation adverse effects in Wistar rats

Glyphosate-based herbicides (GBHs) are the most globally used herbicides raising the risk of environmental exposition. Here, we investigated whether perinatal exposure to low doses of a GBH alters the female reproductive performance, and/or induced second-generation effects related to congenital anomalies or growth alterations. Pregnant rats (F0) received a GBH through food, in a dose of 2 mg (GBH-LD: GBH-low dose group) or 200 mg (GBH-HD: GBH-high dose group) of glyphosate/kg bw/day from gestational day (GD) 9 until weaning. Body weight gain and vaginal canal-opening of F1 females were recorded. Sexually mature F1 females were mated to evaluate their reproductive performance by assessing the pregnancy rate, and on GD19, the number of corpora lutea, the implantation sites (IS) and resorption sites. To analyze second-generation effects on F2 offspring, we analyzed the fetal morphology on GD19, and assessed the fetal length and weight, and the placental weight. GBH exposure neither altered the body weight gain of F1 females, nor vaginal opening onset. Although all GBH-exposed F1 rats became pregnant, a lower number of IS was detected. F2 offspring from both GBH groups showed delayed growth, evidenced by lower fetal weight and length, associated with a higher incidence of small for gestational age fetuses. In addition, higher placental weight and placental index were found in F2 offspring from GBH-HD dams. Surprisingly, structural congenital anomalies (conjoined fetuses and abnormally developed limbs) were detected in the F2 offspring from GBH-HD group. In conclusion, perinatal exposure to low doses of a GBH impaired female reproductive performance and induced fetal growth retardation and structural congenital anomalies in F2 offspring.

[Melatonin for children with insomnia]

Treatment for insomnia with melatonin (MT) in children and adolescents aged 0-17 years has doubled since 2011. The efficacy and safety profile for MT in children has not been determined. Recent clinical trials indicate, that MT only has a clinical effect on sleep latency, not on total sleep time. Furthermore, it has emerged, that proper sleep hygiene can cure the sleep problem in 50% of the children. Typically, the safety evaluation only entails an unclassified report of adverse events. Two long-term studies investigate and dispel the potential influence of MT on puberty.

Growth, sexual and bone development in a boy with bilateral anorchia under testosterone treatment guided by the development of his monozygotic twin

BACKGROUND

Sex steroids are essential for sexual maturation, linear growth and bone development. However, there is no consensus on the optimal timing, dosage and dosage interval of testosterone therapy to induce pubertal development and achieve a normal adult height and bone mass in children with hypogonadism.

CASE PRESENTATION

A monozygotic monochorial male twin pair, of which one boy was diagnosed with anorchia at birth due to testicular regression syndrome was followed from the age of 3 until the age of 18 years. Low dose testosterone substitution (testosterone esters 25 mg/2 weeks) was initiated in the affected twin based on the start of pubertal development in the healthy twin and then gradually increased accordingly. Both boys were followed until age 18 and were compared as regards to linear growth, sexual maturation, bone maturation and bone development. Before puberty induction both boys had a similar weight and height. During puberty, a slightly faster weight and height gain was observed in the affected twin. Both boys ended up however, with a similar and normal (near) adult height and weight and experienced a normal development of secondary sex characteristics. At the age of 17 and 18 years, bone mineral density, body composition and volumetric bone parameters at the forearm and calf were evaluated in both boys. The affected boy had a higher lean mass and muscle cross-sectional area. The bone mineral density at the lumbar spine and whole body was similar. Trabecular and cortical volumetric bone parameters were comparable. At one cortical site (proximal radius), however, the affected twin had a smaller periosteal and endosteal circumference with a thicker cortex.

CONCLUSIONS

In conclusion, a low dose testosterone substitution in bilateral anorchia led to a normal onset of pubertal development and (near) adult height. Furthermore, there was no difference in bone mineral density at the age of 17 and 18 years.