Update on Precocious Puberty in Girls

Diagnosis of Central Precocious Puberty

A thorough history and physical examination including Tanner staging and growth assessments can guide differential diagnosis and aid in the evaluation of precocious puberty. Basal luteinizing hormone levels measured using a highly sensitive assay can be helpful in diagnosing central precocious puberty (CPP). Brain MRI is indicated with males diagnosed with CPP and females under the age of 6 with CPP. As more information becomes available regarding the genetic etiologies of CPP, genetic testing may preclude the need for imaging studies and other hormonal testing, especially in familial cases.

Alterations in Appetite-Regulating Hormones in Girls with Central Early or Precocious Puberty

The prevalence of central precocious puberty (CPP) in girls has increased worldwide and is often associated with obesity in childhood as well as high fat/high glycemic index diets. Evidence suggests that subjects with obesity present with alterations in appetite-regulating hormones. The arcuate and paraventricular nuclei of the hypothalamus are the centers of action of appetite hormones, as well as the location of gonadotropin-releasing hormone (GnRH) neurons, the activation of which results in the onset of puberty. This anatomical proximity raises the question of possible alterations in appetite-regulating hormones in patients with CPP. Furthermore, diet-induced hypothalamic inflammation constitutes a probable mechanism of the pathophysiology of CPP, as well as alterations in appetite-regulating hormones in young children. In this article, we summarize the evidence investigating whether girls with CPP present with alterations in appetite-regulating hormones. We present evidence that leptin concentrations are elevated in girls with CPP, ghrelin concentrations are lower in girls with CPP, nesfatin-1 and orexin-A concentrations are elevated among girls with premature thelarche, and insulin concentrations are increased in girls with early menarche.

Precocious Puberty: Types, Pathogenesis and Updated Management

Precocious puberty (PP) means the appearance of secondary sexual characters before the age of eight years in girls and nine years in boys. Puberty is indicated in girls by the enlargement of the breasts (thelarche) in girls and in boys by the enlargement of the testes in either volume or length (testicular volume = 4 mL, testicular length = 25 mm, or both). Two types of PP are recognized - namely central PP (CPP) and peripheral PP (PPP). This paper aims to describe the clinical findings and laboratory workup of PP and to illustrate the new trends in the management of precocious sexual maturation. Gonadotropin-releasing hormone (GnRH)-independent type (PPP) refers to the development of early pubertal maturation not related to the central activation of the hypothalamic-pituitary-gonadal (HPG) axis. It is classified into genetic or acquired disorders. The most common forms of congenital or genetic causes involve McCune-Albright syndrome (MAS), familial male-limited PP, and congenital adrenal hyperplasia. The acquired causes include exogenous exposure to androgens, functioning tumors or cysts, and the pseudo-PP of profound primary hypothyroidism. On the other hand, CPP is the most common and it is a gonadotropin-dependent form. It is due to premature maturation of the HPG axis. CPP may occur as genetic alterations, such as MKRN3, DLK1, or KISS1;as a part of mutations in the epigenetic factors that regulate the HPG axis, such as Lin28b and let-7; or as a part of syndromes, central lesions such as hypothalamic hamartoma, and others. A full, detailed history and physical examination should be taken. Furthermore, several investigations should be conducted for both types of PP, including the estimation of serum gonadotropins such as luteinizing and follicle-stimulating hormones and sex steroids, in addition to a radiographic workup and thyroid function tests. Treatment depends on the type of PP: Long-acting GnRHa, either intramuscularly or implanted, is the norm of care for CPP management, while in PPP, especially in congenital adrenal hyperplasia, the goal of management is to suppress adrenal androgen secretion by glucocorticoids. In addition, anastrozole and letrozole - third-generation aromatase inhibitors - are more potent for MAS.

Prosopagnosia (face blindness) and child health during the COVID-19 pandemic

Prosopagnosia or 'face blindness' is the inability to recognise people's faces. There are two types: congenital or developmental prosopagnosia, which is the most common, and acquired prosopagnosia, which may occur secondary to brain tumours, stroke or other brain disorders. The authors of this article explored if mask wearing as a result of the restrictions imposed by the coronavirus disease 2019 (COVID-19) pandemic may affect social and developmental outcomes in children, including the development of prosopagnosia. Limited research on this topic is available and, although some relevant publications were found, no definitive evidence of mask-induced prosopagnosia in children was identified. However, nurses should be aware of this issue and discuss coping strategies to support children with the condition. Longitudinal studies on outcomes in children from different age groups who grew up during the COVID-19 pandemic will provide further insight.

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.

The therapeutic role and potential mechanism of EGCG in obesity-related precocious puberty as determined by integrated metabolomics and network pharmacology

Objective

(-)-Epigallocatechin-3-gallate (EGCG) has preventive effects on obesity-related precocious puberty, but its underlying mechanism remains unclear. The aim of this study was to integrate metabolomics and network pharmacology to reveal the mechanism of EGCG in the prevention of obesity-related precocious puberty.

Materials and methods

A high-performance liquid chromatography-electrospray ionization ion-trap tandem mass spectrometry (LC-ESI-MS/MS) was used to analyze the impact of EGCG on serum metabolomics and associated metabolic pathways in a randomized controlled trial. Twelve weeks of EGCG capsules were given to obese girls in this trail. Additionally, the targets and pathways of EGCG in preventing obesity-related precocious puberty network pharmacology were predicted using network pharmacology. Finally, the mechanism of EGCG prevention of obesity-related precocious puberty was elucidated through integrated metabolomics and network pharmacology.

Results

Serum metabolomics screened 234 endogenous differential metabolites, and network pharmacology identified a total of 153 common targets. These metabolites and targets mainly enrichment pathways involving endocrine-related pathways (estrogen signaling pathway, insulin resistance, and insulin secretion), and signal transduction (PI3K-Akt, MAPK, and Jak-STAT signaling pathways). The integrated metabolomics and network pharmacology indicated that AKT1, EGFR, ESR1, STAT3, IGF1, and MAPK1 may be key targets for EGCG in preventing obesity-related precocious puberty.

Conclusion

EGCG may contribute to preventing obesity-related precocious puberty through targets such as AKT1, EGFR, ESR1, STAT3, IGF1, and MAPK1 and multiple signaling pathways, including the estrogen, PI3K-Akt, MAPK, and Jak-STAT pathways. This study provided a theoretical foundation for future research.

The utilization of basal luteinizing hormone in combination with the basal luteinizing hormone and follicle-stimulating hormone ratio as a diagnostic tool for central precocious puberty in girls

PURPOSE

Intravenous gonadotropin-releasing hormone (IV GnRH) testing is the gold standard for confirming a central precocious puberty (CPP) diagnosis. However, this test is not widely available commercially. Therefore, our study aim was to establish cutoff values for basal gonadotropin level and gonadotrophin responses to a 100-μg subcutaneous IV GnRH test that can distinguish between CPP and premature thelarche (PT) to discover a simple method to detect CPP.

METHODS

Girls between the ages of 6 and 8 years who attended the pediatric endocrinology outpatient clinic at our tertiary hospital between 2019 and 2022 were included in this study. They were evaluated for breast development, and a subcutaneous 100-μg GnRH test was administered by measuring the luteinizing hormone (LH) and follicle-stimulating hormone (FSH) levels in blood samples at baseline and then 30, 60, 90, and 120 minutes after injection. CPP is characterized by increased height velocity, advanced bone age, and progression of breast development. The cutoff value for diagnosis of CPP was determined using a receiver operating characteristic (ROC) analysis.

RESULTS

In 86 Thai girls (56 with CPP and 30 with PT), the ROC analysis showed 71.4% and 100% sensitivity and specificity, respectively, for basal LH (cutoff ≥ 0.2 IU/L) plus the basal LH/FSH ratio (cutoff ≥ 0.1). The optimal cutoff values for peak LH (cutoff ≥ 7 IU/L) demonstrated a sensitivity of 94.6% and a specificity of 100%, whereas the LH value at 30 and 60 minutes after injection (cutoff ≥ 6 IU/L) demonstrated sensitivities of 92.9% and 94.6% and a specificity of 100%, respectively.

CONCLUSION

Combining the basal LH (cutoff: 0.2 IU/L) and the basal LH/FSH ratio (cutoff: 0.1) can easily and cost-effectively diagnose CPP in a girl in breast Tanner stage II.

Pediatric and Adolescent Breast Conditions: A Review

Breast conditions in pediatric and adolescent patients vary from benign congenital changes to pathological findings. Although most breast conditions are benign, there are rare cases of malignancy that are important to identify during development. As such, it is critical to understand the classification and management of the different pediatric and adolescent breast conditions that might present to clinicians who care for pediatric and adolescent patients. In this review, congenital, benign, and malignant pediatric/adolescent breast conditions are discussed.

Mechanism of leptin-NPY on the onset of puberty in male offspring rats after androgen intervention during pregnancy

OBJECTIVES

The time of onset of puberty has been increasingly earlier, but its mechanism is still unclear. This study aimed to reveal the mechanism of leptin and NPY in the onset of puberty in male offspring rats after androgen intervention during pregnancy.

METHODS

Eight-week-old specific pathogen-free (SPF) healthy male Sprague-Dawley (SD) rats and 16 female SD rats were selected and caged at 1:2. The pregnant rats were randomly divided into the olive oil control group (OOG) and testosterone intervention group (TG), with 8 rats in each group. Olive oil and testosterone were injected from the 15th day of pregnancy, for a total of 4 injections (15th, 17th, 19th, 21st day). After the onset of puberty, the male offspring rats were anesthetized with 2% pentobarbital sodium to collect blood by ventral aorta puncture and decapitated to peel off the hypothalamus and abdominal fat. Serum testosterone (T), free testosterone (FT), dihydrotestosterone (DHT), dehydroepiandrosterone (DHEA), sex hormone binding globulin (SHBG), and leptin were detected by ELISA, and then the free androgen index (FAI) was calculated. The mRNA levels of androgen receptor (AR), estrogen receptor α (ERα), NPY, leptinR, and NPY2R in the hypothalamus and abdominal fat were detected by RT-PCR. Protein expression levels of AR, ERα, NPY, leptinR, and NPY2R in the arcuate nucleus (ARC) of the hypothalamus were detected by immunohistochemistry.

RESULTS

The time of onset of puberty was significantly earlier in the TG than in the OOG (P< 0.05) and was positively correlated with body weight, body length, abdominal fat, and leptinR mRNA levels in adipose tissue in the OOG (P< 0.05), while it was positively correlated with serum DHT and DHEA concentrations and FAI and AR mRNA levels in the hypothalamus in the TG (P< 0.05). The NPY2R mRNA level and protein expression levels of ERα, NPY2R, and leptinR in the TG were significantly higher than those in the OOG, while the protein expression levels of AR and NPY in the TG were significantly lower than those in the OOG (P< 0.05).

CONCLUSIONS

Testosterone intervention during pregnancy led to an earlier onset of puberty in male offspring rats, which may render the male offspring rats more sensitive to androgens, leptin, and NPY at the onset of puberty.

Oestrogenic Activity in Girls with Signs of Precocious Puberty as Exposure Biomarker to Endocrine Disrupting Chemicals: A Pilot Study

The relationship between endocrine disrupting chemical (EDC) exposure and Precocious Puberty (PP) was investigated in this pilot study, involving girls with signs of PP (P) and pre-pubertal girls (C). Risk factors for PP were assessed through questionnaires, while 17β-oestradiol (E2) levels and oestrogenic activity were quantified on sera. The oestrogenic activity, expressed as E2 equivalent concentration (EEQ), was applied as EDC exposure biomarker. Questionnaires showed a low EDC knowledge, a high EDC exposure, and a potential relationship between some habits at risk for EDC exposure and PP. EEQs were similar between C and P; however, they were significantly higher in girls living in an urban environment than in girls living in a rural environment, suggesting a potential higher EDC exposure in cities. The results of this pilot study highlighted the need to raise awareness on EDCs and can be considered a starting point to clarify the relationship between EDC exposure and PP.

Clinical, Endocrine and Neuroimaging Findings in Girls With Central Precocious Puberty

CONTEXT

The etiology of central precocious puberty (CPP) includes a spectrum of conditions. Girls younger than age 6 years with CPP should undergo cranial magnetic resonance imaging (MRI), but it remains controversial whether all girls who develop CPP between the ages of 6 and 8 years require neuroimaging examination.

OBJECTIVE

To investigate the frequency of brain MRI abnormalities in girls diagnosed with CPP and the relationship between maternal factors, their age at presentation, clinical signs and symptoms, hormonal profiles, and neuroimaging findings.

METHODS

Data were collected between January 2005 and September 2019 from 112 girls who showed clinical pubertal progression before 8 years of age who underwent brain MRI.

RESULTS

MRI was normal in 47 (42%) idiopathic (I) scans, 54 (48%) patients had hypothalamic-pituitary anomalies (HPA) and/or extra-HP anomalies (EHPA), and 11 (10%) had brain tumors or tumor-like conditions (BT/TL), including 3 with neurological signs. Associated preexisting disorders were documented in 16. Girls with BT/TL had a higher LH peak after GnRH test (P = 0.01) than I, and those older than age 6 years had a higher craniocaudal diameter of the pituitary gland (P = 0.01); their baseline FSH and LH (P = 0.004) and peak FSH (P = 0.01) and LH (P = 0.05) values were higher than I. Logistic regression showed maternal age at menarche (P = 0.02) and peak FSH (P = 0.02) as BT/TL risk factors.

CONCLUSIONS

MRI provides valuable information in girls with CPP by demonstrating that fewer than half have a normal brain MRI and that few can have significant intracranial lesions after the age of 6, despite the absence of suggestive neurological signs.

Investigation on the Correlation of Anxiety Degree with Family Atmosphere in Children with Precocious Puberty

Objective

This research sets out to explore the correlation of anxiety degree with family atmosphere in children with precocious puberty (PP), so as to provide a reference for future treatment of PP.

Methods

Eighty-one cases of PP were visited between January 2021 and March 2021, and their direct relatives were selected as the research population for retrospective analysis. After admission, children and their direct relatives completed a questionnaire survey on the quality of life and social anxiety of children with PP. Children were assigned to the research group and the control group based on their anxiety scores. The intergroup differences in daily activities, diet, and family status, as well as children's and parents' psychological status, were identified, and the relationship between anxiety degree in PP children and family atmosphere was discussed.

Results

The children's anxiety score was (6.17 ± 4.26), and they were divided into groups according to the median, with 30 cases in the research group and 51 cases in the control group. The two cohorts were similar in dietary status and children's physiological status (P > 0.05); however, the research group exhibited a greater number of cases who used electronic products for 2-3 h daily and watched romantic TV series (movies). The daily exercise time of the research group is lower than that of the control group (P < 0.05). In the research group, the monthly family income and the number of family companions and very harmonious families were significantly lower, while the number of divorces or remarriages increased (P < 0.05). The survey results on parents' psychological status also showed better psychological states in patients in the control group (P < 0.05).

Conclusion

The anxiety level of PP children is closely related to the family atmosphere. In future clinical treatment of children with PP, it will also be necessary to pay attention to and adjust the family relationship of the children, which is of great significance for relieving PP-associated anxiety.

The Possible Association between Phthalates and Bisphenol A Exposure and Idiopathic Precocious Puberty in Egyptian Girls

BACKGROUND: Bisphenol A (BPA) and phthalates are utilized in large spectrum of plastics, as polyvinyl chloride as well as personal products, medical equipment, and epoxy resins. Phthalate and bisphenol A are the most common endocrine disrupting chemicals that interrupt the endocrine system and cause developmental, reproductive, neurological, and immune disturbances in humans. However, the relation between phthalates and bisphenol A and precocious puberty (PP) in human is still controversial. AIM: Consequently, the present study aimed to detect and investigate the association between exposure to bisphenol A and monobutyl phthalate (MBP) and precocious puberty in Egyptian girls. METHODS: Urine samples were collected from 100 young females. The subjects were divided into two major groups, precocious puberty group consisted of 60 young females diagnosed by an endocrine pediatric specialist and controls consisted of 40 normal young females matched in age and demographic characters. In urine, MBP and bisphenol A (BPA) were measured with high-performance liquid chromatography. RESULTS: The mean concentration of MBP level was 22.758 ± 6.216 for the PP group and 15.283 ± 6.262 for controls with statistical difference between the studied groups (p < 0.001). Furthermore, the mean concentration of BPA was 405.02 ± 223.54 for the PP group and 97.95 ± 55 for controls with significant difference between groups (p < 0.001). CONCLUSION: The present study found that idiopathic precocious puberty in young females was associated with high phthalate metabolites and bisphenol A levels in urine.

Assessment of Gonadotropin Concentrations Stimulated by Gonadotropin-Releasing Hormone Analog by Electrochemiluminescence in Girls with Precocious Puberty and Premature Thelarche

OBJECTIVE

The aim of this study is to determine the cutoff values of gonadotropin response to gonadotropin-releasing hormone analogs (GnRHas) corresponding to the activation of the hypothalamic-pituitary-gonadal axis that could differentiate central precocious puberty (CPP) from premature thelarche (PT) and using the electrochemiluminescence assay method.

METHODS

A total of 49 girls underwent the stimulation test with an intramuscular injection of 3.75 mg leuprolide acetate. Based on the clinical and laboratory characteristics, they were divided into two groups: CPP (n = 22) and PT (n = 27). Baseline estradiol, luteinizing hormone (LH), and follicle-stimulating hormone (FSH) were collected before GnRHa administration and LH and FSH at 60 and 120 min, respectively, after GnRHa administration.

RESULTS

The girls with CPP presented an increased height Z-score, advanced bone age, and higher baseline LH, FSH, estradiol, and LH/FSH ratio in relation to PT (p < 0.001). Stimulated LH differed significantly between the two groups, and the LH cutoff values were ≥4.29 IU/L (p < 0.001) and ≥3.95 IU/L at 60 and 120 min, respectively (p < 0.001). The LH peak was found at 60 min after stimulation.

CONCLUSIONS

The GnRHa test is effective in distinguishing CPP from PT, and a single sampling, at 60 min, with LH concentrations above 4.29 may be the parameter of choice with the advantage of greater convenience and practicality.

Phthalate's multiple hormonal effects and their supplementary dietary regulation scheme of health risks for children

Four common phthalic acid esters (PAEs), namely, butylbenzyl phthalate (BBzP), dibutyl phthalate (DBP), di(2-ethylhexyl) phthalate (DEHP), and di-n-octyl phthalate (DNOP) that are known to affect children upon exposure, were selected, and the hormone effects were explored during different supplementary food intakes by using methods such as factorial design experiment, molecular docking, and dynamics simulation techniques. A supplementary diet regulation scheme to prevent health risks of PAEs was constructed to avoid or mitigate the hormonal effects in children exposed to PAEs. Firstly, the MM/PBSA binding energy of PAEs with single hormone receptors and multiple hormone receptor complexes was calculated. In addition, 10 foods were selected as external interference conditions to carry out dynamic simulation, which showed that kiwi fruit and broccoli can effectively alleviate the PAEs' hormone effects. Furthermore, inference of the metabolic process of DEHP found that the supplementary diets could effectively promote the metabolism of PAEs. Finally, based on the mechanism analysis, it was confirmed that the selected supplementary diets could inhibit the binding process. This study aims to explore the role of supplementary diets in regulating various PAEs' hormone effects and thereby provide theoretical support for slowing down hormonal effects in children.

Association of Early Pubertal Onset in Female Rats With Inhalation of Lavender Oil

BACKGROUND

Central precocious puberty (CPP) is caused by early activation of the hypothalamic-pituitary-gonadal axis but its major cause remains unclear. Studies have indicated an association between chronic environmental exposure to endocrine-disrupting chemicals and pubertal onset. Essential oil is widely used in homes worldwide for relief of respiratory symptoms, stress, and/or sleep disturbance.

METHODS

To evaluate this association, we compared the hormone levels and timing of vaginal opening (VO) in female rats exposed to lavender oil (LO) through different routes (study groups: control, LO nasal spray [LS], and indoor exposure to LO [LE]) during the prepubertal period. The body weights of the animals were also compared every 3 days until the day of VO, at which time gonadotropin levels and internal organ weights were assessed.

RESULTS

The LS group showed early VO at 33.8 ± 1.8 days compared with the control (38.4 ± 2.9 days) and LE (36.6 ± 1.5 days) groups. Additionally, luteinizing hormone levels were significantly higher in the LE and LS groups than those in the control group. Body weights did not differ significantly among the groups.

CONCLUSION

Inhalation exposure to an exogenic simulant during the prepubertal period might trigger early pubertal onset in female rats. Further evaluation of exposure to other endocrine-disrupting chemicals capable of inducing CPP through the skin, orally, and/or nasally is warranted.

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.

Short-term serum and urinary changes in sex hormones of healthy pre-pubertal children after the consumption of commercially available whole milk powder: a randomized, two-level, controlled-intervention trial in China

Progesterone was found in commercial milk. After consuming this milk, compared with the control, serum progesterone levels after 3 h and urinary pregnanediol levels within 4 h increased, but those in urine after 48 h had no significant change.

Diagnosis and management of precocious sexual maturation: an updated review

The classic definition of precocious sexual maturation is the development of secondary sexual characteristics before 8 years of age in girls and before 9 years of age in boys. It is classified as central precocious puberty when premature maturation of the hypothalamic-pituitary-gonadal axis occurs, and as peripheral precocious puberty when there is excessive secretion of sex hormones, independent of gonadotropin secretion. Precocious sexual maturation is more common in girls, generally central precocious puberty of idiopathic origin. In boys, it tends to be linked to central nervous system abnormalities. Clinical evaluation should include a detailed history and physical examination, including anthropometric measurements, calculation of growth velocity, and evaluation of secondary sexual characteristics. The main sign to suspect the onset of puberty is breast tissue development (thelarche) in girls and testicular enlargement (≥4 mL) in boys. Hormonal assessment and imaging are required for diagnosis and identification of the etiology. Genetic testing should be considered if there is a family history of precocious puberty or other clinical features suggestive of a genetic syndrome. Long-acting gonadotropin-releasing hormone analogs are the standard of care for central precocious puberty management, while peripheral precocious puberty management depends on the etiology.Conclusion: The aim of this review is to address the epidemiology, etiology, clinical assessment, and management of precocious sexual maturation. What is Known: • The main sign to suspect the onset of puberty is breast tissue development (thelarche) in girls and testicular enlargement (≥4 mL) in boys. The classic definition of precocious sexual maturation is the development of secondary sexual characteristics before 8 years of age in girls and before 9 years of age in boys. • Long-acting gonadotropin-releasing hormone agonist (GnRHa) is the standard of care for CPP management, and adequate hormone suppression results in the stabilization of pubertal progression, a decline in growth velocity, and a decrease in bone age advancement. What is New: • Most cases of precocious sexual maturation are gonadotropin-dependent and currently assumed to be idiopathic, but mutations in genes involved in pubertal development have been identified, such as MKRN3 and DLK1. • A different preparation of long-acting GnRHa is now available: 6-month subcutaneous injection.

Disorders of Puberty in Girls

Puberty is the process through which reproductive competence is achieved and comprises gonadarche and adrenarche. Breast development is the initial physical finding of pubertal onset in girls and typically occurs between 8 and 13 years. Menarche normally occurs 2 to 3 years after the onset of breast development. Pubertal onset is controlled by the gonadotropin-releasing hormone pulse generator in the hypothalamus; however, environmental factors such as alterations in energy balance and exposure to endocrine-disrupting chemicals can alter the timing of pubertal onset. Improvement in nutritional and socioeconomic conditions over the past two centuries has been associated with a secular trend in earlier pubertal onset. Precocious puberty is defined as onset of breast development prior to 8 years and can be central or peripheral. Delayed puberty can be hypogonadotropic or hypergonadotropic and is defined as lack of breast development by 13 years or lack of menarche by 16 years. Both precocious and delayed puberty may have negative effects on self-esteem, potentially leading to psychosocial stress. Patients who present with pubertal differences require a comprehensive assessment to determine the underlying etiology and to devise an effective treatment plan.

Association between Dietary Habits and Parental Health with Obesity among Children with Precocious Puberty

Precocious puberty, resulting in various physical, mental, and social changes, may have negative consequences for children and their families. In this study, we investigated whether there were differences between parental obesity, children's and parent's awareness of body shape, and dietary habits according to obesity levels in children with precocious puberty. A total of 193 children (93.3% girls) diagnosed with precocious puberty were classified into three groups according to their obesity levels. Negative body shape awareness and dissatisfaction were significantly higher in the obese group than in the normal-weight group, and parents were more likely to perceive their children as fat than the children themselves. In addition, the obesity rate of parents in the obese group was higher, and the body mass indexes of children and parents were significantly correlated. The nutrition quotients (NQs) were revealed to be significantly lower in the obese group with significantly lower scores. The significant factors related to obesity were the awareness of a fatty body image and dissatisfaction, obesity of the parents, and the NQ. The results show that obese children with precocious puberty were more vulnerable to negative lifestyle, family environment, and self-esteem effects than their normal-weight peers. Therefore, various interventions, such as environmental management, psychological support, and nutrition education, are needed that focus on the obesity and health conditions of children with precocious puberty.

Factors affecting bone maturation in Chinese girls aged 4-8 years with isolated premature thelarche

Background

In isolated premature thelarche (IPT) girls, bone age (BA) is considered consistent with chronological age. However, some IPT girls confirmed by gonadotropin-releasing hormone (GnRH) stimulation test could show another trend. We analysed BA and possible potentiating factors in a selected group of girls aged 4–8 years with IPT.

Methods

IPT girls confirmed by GnRH stimulation test aged 4–8 years hospitalized from January 2015 to April 2018 at Shenzhen Children’s Hospital were included in this retrospective study. They were divided into two groups with advanced BA of 2 years as the cut-off. Body mass index (BMI) and hormone levels were the main outcome measures, and regression analysis was used to identify independent risk factors. IPT girls were divided into subgroups according to the levels of BMI standard deviation score (SDS), insulin-like growth factor-1 (IGF-1) SDS and dehydroepiandrosterone sulfate (DHEAS) SDS for comparisons of advanced BA.

Results

Overall, 423 subjects were included and classified into the advanced BA group (48.7%, n = 206) and control group (51.3%, n = 217). The advanced BA group had significantly higher BMI SDS, serum DHEAS SDS, IGF-1 SDS, androstenedione and fasting insulin and significantly lower sex hormone binding globulin (all p < 0.001). Serum IGF-1 SDS (OR = 1.926, p<0.001), BMI SDS (OR = 1.427, p = 0.001) and DHEAS SDS (OR = 1.131, p = 0.005) were independent risk factors for significantly advanced BA. In the multiple linear regression model, serum IGF-1 SDS, BMI SDS and DHEAS SDS were the strongest predictors of advanced BA, accounting for 19.3% of the variance. According to BMI, 423 patients were classified into three groups: normal weight (56.03%, n = 237), overweight (19.15%, n = 81) and obesity (24.82%, n = 105). The proportion of advanced BA in obesity group was significantly higher than those of normal weight and overweight groups (χ² = 18.088, p<0.001). In the subgroup with normal weight, higher serum IGF-1 SDS (p = 0.009) and DHEAS SDS (p = 0.003) affected BA advancement independent of BMI SDS.

Conclusions

Girls with IPT confirmed by GnRH stimulation test aged 4–8 years might have significantly advanced BA. Obesity was highly associated with advanced BA. Age-specific serum IGF-1 SDS and DHEAS SDS were risk factors for BA advancement independent of BMI.

[Association of body fat ratio with precocious puberty in girls]

OBJECTIVE

To study the association of body fat ratio with precocious puberty in girls. Previous studies have shown that body mass index (BMI) is associated with the girls' age of puberty but have not revealed the association of body fat ratio with age of puberty.

METHODS

Based on the consensus on the diagnosis and treatment of central precocious puberty (CPP), 128 children with precocious puberty who were admitted to the hospital from July to August, 2017, were divided into a CPP group with 87 children and a peripheral precocious puberty (PPP) group with 41 children. A total of 51 girls without any puberty development signs were enrolled as the control group. Dual-energy X-ray absorptiometry was used to measure the body fat ratios of upper limbs, legs, trunk, android area, gynoid area, and the whole body. The association between body fat ratios and precocious puberty was analyzed with reference to age, BMI, BMI-Z score, bone age, ovarian volume, and hormone levels.

RESULTS

Compared with the control group, the CPP and PPP groups had significantly higher body fat ratios of upper limbs, legs, trunk, android area, gynoid area, and the whole body, legs/whole body fat ratio, and (upper limbs+legs)/trunk fat ratio (P<0.05), while there were no significant differences in the above body fat ratios and fat distribution indicators between the CPP and PPP groups (P>0.05). For the girls with precocious puberty, the high body fat ratio group had significantly higher luteinizing hormone (LH) base value, luteinizing hormone releasing hormone (LHRH)-stimulated LH peak value, and LH/follicle-stimulating hormone peak value than the low body fat ratio group (P<0.05). Compared with the control group, both the high body fat ratio and low body fat ratio groups had a significantly higher LH base value (P<0.05).

CONCLUSIONS

The increase in body fat may be a factor inducing precocious puberty in girls, but further studies are needed to determine the mechanism.