Gonadotropin releasing hormone agonist treatment to increase final stature in children with precocious puberty: a meta-analysis

Effect and safety of aromatase inhibitors for the treatment of short stature in male children and adolescents: a meta-analysis of randomized controlled trials

This study is to evaluate the efficacy and safety of aromatase inhibitors (AIs) in the treatment of short stature in male children and adolescents. Pooled estimates of final or near-final height, predicted adult height (PAH), bone age, and potential side effects were calculated using a random-effects model or fixed-effects model. Our search identified 11 studies with a total of 463 participants. AI was associated with a significant increase in final or near-final height (weight mean difference (WMD)=3.61 cm, 95 % CI: 0.96, 6.26; p<0.001) and PAH (WMD=2.52 cm, 95 % CI: 0.32, 4.72; p=0.025) compared to other treatment. The use of AI showed an increased risk of minor side effects (risk ratio (RR)=2.90, 95 % CI: 1.15, 7.33; p=0.025), but no severe adverse effects were reported. Subgroup analysis, stratified by patient disease, revealed that AI significantly enhanced final or near-final height in both patients with idiopathic short stature (ISS) and those with constitutional delay of growth and puberty (CDGP). AIs may contribute to height increase in male children and adolescents with short stature, without significantly advancing bone age. However, the increased risk of minor side effects indicates the need for careful monitoring during AI therapy.

Growth pattern, growth deceleration, and relevant predictors in girls treated with GnRHa: a retrospective longitudinal study

OBJECTIVES

This study aimed to analyze the height growth pattern and the incidence of significant growth deceleration in girls with CPP and EFP on GnRHa treatment, and thereby identify relevant predictors of growth deceleration.

METHODS

The data of 99 girls diagnosed with CPP and 47 girls with EFP were included in this retrospective analysis. The incidence of growth deceleration was calculated in both the first and second years. Multivariate logistic regression analysis was used to identify predictors indicative of growth deceleration.

RESULTS

Growth velocity (GV) trajectories showed gradual decreases to the nadir at 18 months of treatment, and then they recovered till the 24th month of treatment, especially in girls with CPP. Nevertheless, the recovery was significantly greater in the CPP group than EFP. In the first year, no significant difference in the incidence of growth deceleration was found between the CPP group and the EFP group [17.35 vs. 25.53 %, p=0.249]; in the second year, the CPP group had a lower incidence than the EFP group [42.86 vs. 76.92 %, p=0.027]. The multivariate logistic regression analysis suggested that bone age (BA) was an independent predictor of growth deceleration (OR=2.264, 95 % CI: 1.268-4.042, p=0.006). The result of ROC curves showed the cut-off value of BA was 11.05 years.

CONCLUSIONS

GV varies at different periods during GnRHa treatment. GnRHa should be used with more caution for EFP treatment than for CPP. BA can be used to predict the occurrence of growth deceleration during GnRHa treatment.

Treatment of Central Precocious Puberty with a Focus on Girls

The age of thelarche has declined in the past few decades but not the age of menarche. This is important when assessing girls who present with breast development between 6 and 8 years because not all of them will need treatment. The decision for treatment depends on age, bone age (BA), rate of pubertal progression, height velocity, psychosocial factors, and predicted adult height (PAH), with the caveat that height predictions are not precise and BA interpretation is variable.

Unstimulated Luteinizing Hormone for Assessment of Suppression during Treatment of Central Precocious Puberty with 6-Month Subcutaneous Leuprolide Acetate: Correlations with Clinical Response

INTRODUCTION

Phase 3 trial of 6-month subcutaneous leuprolide acetate (SC-LA) in children with central precocious puberty (CPP) demonstrated efficacy and safety. The aims of this secondary analysis were to evaluate unstimulated luteinizing hormone (LH) as efficacy measure, assess clinical suppression metrics, and present biochemical and clinical data for subgroups not achieving hormone suppression.

METHODS

Sixty-two children with treatment-naïve CPP received 2 doses of 45 mg SC-LA at 24-week intervals. Unstimulated and GnRH-stimulated LH, E2, and T concentrations were measured. Clinical measures included bone age (BA) and predicted adult height (PAH).

RESULTS

Eighty-four percentage and 86% of children achieved unstimulated LH <1 IU/L at weeks 24 and 48, respectively. Of 8 children not achieving unstimulated LH <1 IU/L at week 24 that completed the study, all showed a lack of pubertal stage progression and stable/decreased BA to chronological age ratio (BA/CA). Received operating characteristic (ROC) analyses suggested unstimulated LH is a good diagnostic predictor of GnRH-stimulated LH <4 IU/L at weeks 24 and 48 (AUC = 0.88). Across all children, mean BA/CA improved from 1.4 (screening) to 1.3 (week 48) and mean PAH increased by 3 cm. Of 7 girls not achieving stimulated LH <4 IU/L at week 24, all achieved E2 <10 pg/mL, showed a lack of pubertal stage progression, and had stable or decreased BA/CA by week 48. Additionally, 6/7 had increased PAH by week 48 and 4 had unstimulated LH <1 IU/L.

CONCLUSION

Unstimulated LH has value as an efficacy measure and concentrations <1 IU/L may be an adequate surrogate of treatment response in children with CPP. All children who completed the study had evidence of pubertal suppression.

The effects of gonadotropin-releasing hormone agonist on final adult height among girls with early and fast puberty

Introduction

This study aimed to explore the impact of gonadotropin-releasing hormone agonists (GnRHa) on final adult height (FAH) in girls with early and fast puberty.

Methods

A retrospective study was conducted by reviewing data from the medical records of the Pediatric Endocrinology Clinics between January 1, 2010, and December 31, 2020, at MacKay Children's Hospital. The treatment group included 109 patients who received 3.75 mg monthly for at least 1 year, whereas the control group consisted of 95 girls who received no treatment.

Results

The treatment group was significantly older at the time of inclusion(chronological age (CA1), treatment vs. control, 8.7 vs. 8.4 years, p < 0.001), had a more advanced bone age (BA) (BA1, 11.5 vs. 10.8 years, p < 0.001), BA1-CA1 (2.7 vs. 2.2 years, p < 0.001), and shorter predicted adult height (PAH1) (153.3 vs. 157.1 cm, p = 0.005) that was significantly lower than their target height (Tht)(PAH1-Tht, -3.9 vs. -1.3 cm, p = 0.039). The FAHs of the GnRHa and the control group were similar (157.0 vs. 156.7 cm, p = 0.357) and were not significantly different from their Tht (FAH vs. Tht in the GnRHa group, 157.0 vs. 157.0 cm; control group, 156.7 vs. 157.0 cm). In the subgroup analysis, FAH was significantly higher after GnRHa treatment in those with PAH1 less than 153 cm and Tht (154.0 vs. 152.0 cm, p = 0.041), and those whose CA1 was between 8 and 9 years (158.0 vs. 155.4 cm, p = 0.004). We defined satisfactory FAH outcome as FAH-PAH1≥5 cm and significant factors were GnRHa therapy, PAH1 shorter than their Tht, age younger than 9 years, and faster growth velocity during the first year.

Discussion

GnRHa is effective in restoring the Tht in some early and fast pubertal girls, especially in those with poorly PAH (PAH lower than 153 cm and shorter than their target height). A younger age at initiation of treatment and a faster growth velocity during treatment are associated with a better height gain.

Analysis of serum insulin-like growth factor-1, fibroblast growth factor 23, and Klotho levels in girls with rapidly progressive central precocious puberty

To study the levels of serum insulin-like growth factor 1 (IGF-1), fibroblast growth factor 23 (FGF23), and Klotho, and to study their relationship with girls with rapidly progressive central precocious puberty (RP-CPP). This is a cross-sectional study on the progression rate of central precocious puberty in girls, who complained of breast development before the age of 8 years and were followed between June 2021 and June 2022. At the same time, 28 healthy girls less than 8 years old who had not started puberty were recruited as the control group. The physical examination and laboratory evaluation of each group was completed. Only patients with CPP received pelvic ultrasound examination and bone age test. Bone age index (BAI), basal LH levels (BLH), basal LH levels/basal FSH levels (BFSH), peak LH (PLH)/peak FSH (PFSH), IGF-1, Klotho, FGF23, and ovarian volume in the RP-CPP group were higher than those in slowly progressive CPP (SP-CPP) group. In the RP-CPP group, IGF-1 was correlated with Klotho, FGF23, and BLH; Klotho was correlated with FGF23 and BLH; FGF23 was correlated with BLH.

CONCLUSION

The BLH, FGF23, Klotho, and IGF-1 have a certain correlation with RP-CPP, which may play an important role in the speed of girls' sexual development.

WHAT IS KNOWN

• The association between IGF-1 and RP-CPP.

WHAT IS NEW

• We found the association between FGF23, Klotho and RP-CPP.

Approach to the Patient: Central Precocious Puberty

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

Physiological and Pharmacological overview of the Gonadotropin Releasing Hormone

Gonadotropin-releasing Hormone (GnRH) is a decapeptide responsible for the control of the reproductive functions. It shows C- and N-terminal aminoacid modifications and two other distinct isoforms have been so far identified. The biological effects of GnRH are mediated by binding to high-affinity G-protein couple receptors (GnRHR), showing characteristic very short C tail. In mammals, including humans, GnRH-producing neurons originate in the embryonic nasal compartment and during early embryogenesis they undergo rapid migration towards the hypothalamus; the increasing knowledge of such mechanisms improved diagnostic and therapeutic approaches to infertility. The pharmacological use of GnRH, or its synthetic peptide and non-peptide agonists or antagonists, provides a valid tool for reproductive disorders and assisted reproduction technology (ART). The presence of GnRHR in several organs and tissues indicates additional functions of the peptide. The identification of a GnRH/GnRHR system in the human endometrium, ovary, and prostate has extended the functions of the peptide to the physiology and tumor transformation of such tissues. Likely, the activity of a GnRH/GnRHR system at the level of the hippocampus, as well as its decreased expression in mice brain aging, raised interest in its possible involvement in neurogenesis and neuronal functions. In conclusion, GnRH/GnRHR appears to be a fascinating biological system that exerts several possibly integrated pleiotropic actions in the complex control of reproductive functions, tumor growth, neurogenesis, and neuroprotection. This review aims to provide an overview of the physiology of GnRH and the pharmacological applications of its synthetic analogs in the management of reproductive and non-reproductive diseases.

Using change in predicted adult height during GnRH agonist treatment for individualized treatment decisions in girls with central precocious puberty

OBJECTIVES

It is important to understand what variables influence change in predicted adult height (PAH) throughout GnRHa treatment for central precocious puberty (CPP) to individualize treatment decisions and optimize care.

METHODS

Changes in PAH, chronological age (CA), bone age (BA), BA/CA, and height velocity (HV) were evaluated in girls with CPP throughout treatment with leuprolide acetate (n=77). A second analysis focused on changes in the 3 years preceding the first observed BA of ≥12 years. Relationships were characterized using plot inspection and linear mixed-effects analyses. Association between treatment duration and last assessed PAH was examined using multiple linear regression models.

RESULTS

BA/CA and HV showed a nonlinear change during treatment, with the largest changes and improvement in PAH observed in the first 6-18 months. Rate of BA advancement tended to decrease more slowly in girls initiating treatment at a younger BA. On-treatment change in PAH was predicted by concurrent BA/CA change, HV, and BA, as well as CA at treatment initiation. Last assessed PAH was positively associated with longer treatment durations (primary/exploratory models cut-offs of ≥33/≥55 months).

CONCLUSIONS

These findings support individualized monitoring during GnRHa treatment. Initial response should be interpreted with caution until 6-18 months after treatment initiation and failure should not be assumed based on continued bone maturation in girls starting therapy at a younger age. Treatment cessation should not be automatically based on a diminishing change in PAH or HV, as ongoing treatment may result in continued increase or maintenance of PAH.

Height benefit of GnRH agonists after age 8 in a Portuguese cohort of central precocious puberty

OBJECTIVE

Idiopathic central precocious puberty (iCPP) is common in paediatric endocrinology. Gonadotropin-releasing hormone agonists (GnRHa) are safe, but the effect on final height and the ideal timing for treatment remains controversial. This study aims to assess the effectiveness of GnRHa on growth outcomes in girls with iCPP treated before and after the age of 8 years old.

DESIGN AND PATIENTS

This retrospective longitudinal study evaluated data from Portuguese girls with iCPP who completed treatment between 2010 and 2021.

MEASUREMENTS

Auxological and clinical characteristics were compared according to age at treatment onset.

RESULTS

A cohort of 134 girls with iCPP, was divided into early treatment (ET) (<8 years, n = 48) and later treatment (LT) groups (≥8 years, n = 86). In both groups, most children presented with Tanner II and III. Tanner IV was more frequent in LT group (p = .003). At the end of treatment, predicted adult height increased in both groups (ET p = .032; LT p = .04) and bone age significantly slowed down in all participants (p = .008, p = .034). The height gain was greater in the ET group, but without significant differences (p = .065).

CONCLUSIONS

Treatment with GnRHa improved final height in all girls with iCPP, even when initiated after 8 years. To achieve better outcomes, treatment should be provided promptly after diagnosis.

Benefits from the first year of GnRHa therapy in boys with idiopathic central precocious puberty when initiating treatment after age 9 years: findings from a real-world retrospective study

BACKGROUND

GnRHa treatment was established for improving final adult height (FAH) in children presenting with Idiopathic central precocious puberty (ICPP) up to age 8, while several controversies remained for older age groups. The primary objective was to evaluate whether boys diagnosed with ICPP over 9 years of chronological age (CA) could achieve a height benefit from GnRHa treatment.

METHODS

We retrospectively evaluated the medical records of 23 boys treated for idiopathic central precocious puberty between January 2018 and January 2021 at Jiangsu Children's Medical Center. All patients started treatment with intramuscular depot GnRHa at a dose of 80-100 μg/kg, followed by continuous intramuscular injection every 28 days at a dose of 60-80 μg/kg. The hormonal parameters, bone age/chronological age ratio, FAH, growth velocity (GV), tanner staging and body mass index (BMI) were assessed during the treatment period.

RESULTS

After one course of treatment (3 months), the basal FSH and testosterone levels were reduced, while the basal LH value was not significantly changed compared with those before treatment. Furthermore, the mean BA/CA ratio reduction was statistically significant at month 12. The mean PAH following administration of GnRHa after 12 months was statistically improved compared with those at baseline. In addition, the clinical sign of puberty and GV were significantly improved and the BMI remained unchanged as desired at month 12.

CONCLUSIONS

This analysis highlighted the positive outcome on the decrease in the rate of bone maturation, with a favorable effect on progression of clinical signs of puberty. Furthermore, our study confirmed PAH was improved even in the older children at onset of treatment (ages 9-10), emphasizing the importance of personalized treatment in such population.

Arsenic exposure during juvenile and puberty significantly affected reproductive system development of female SD rats

Infertility affects about 10-15% couples over the world, among which a large number of cases the underlying causes are still unclear. Recent studies suggest that environmental factors may play an important role in these idiopathic infertilities. Arsenic is a heavy metal found in drinking water over the world. Its effect on the development of female reproductive system at the environmental-relevant levels is still largely unknown. To test the hypothesis that arsenic exposure during juvenile and puberty may affect sex maturation and female reproductive system development, SD rats of 3 weeks of age were exposed to arsenic with environmental-relevant levels (0, 0.02, 0.2, or 2 mg/L, n = 16/group) through drinking water for about 44 days until the rats reached adulthood (65 days of age). Arsenic exposure significantly reduced the weights of both ovary and uterus without affecting the body weight. Also, arsenic exposure disturbed estrus cycles and reduced the numbers of primordial follicles and corpora lutea while increased atretic follicles. In addition, arsenic reduced serum levels of estradiol, progesterone and testosterone but increased LH and FSH levels in dose-dependent manners. QPCR and Western blot experiments indicated arsenic selectively down-regulated ovarian steroidogenic-related proteins FSHR, STAR, CYP17A1, HSD3B1 and CYP19A1 and signaling molecules PKA-ERK-JNK-cJUN, without affecting AKT and CREB. As about reproductive capacity, arsenic-exposed dams had smaller pups, reduced litter size and lower number of male pups without a change in female pups. In conclusion, juvenile and pubertal arsenic exposures at environmental-relevant levels significantly reduced reproductive functions and capacity by adult. Since the lowest effective dose is very close to the government safety standards, the relevancy of arsenic over exposure to reproductive defects in human deserves further study.

The Role of Pediatric Nutrition as a Modifiable Risk Factor for Precocious Puberty

Puberty is a critical phase of growth and development characterized by a complex process regulated by the neuroendocrine system. Precocious puberty (PP) is defined as the appearance of physical and hormonal signs of pubertal development at an earlier age than is considered normal. The timing of puberty has important public health, clinical, and social implications. In fact, it is crucial in psychological and physical development and can impact future health. Nutritional status is considered as one of the most important factors modulating pubertal development. This narrative review presents an overview on the role of nutritional factors as determinants of the timing of sexual maturation, focusing on early-life and childhood nutrition. As reported, breast milk seems to have an important protective role against early puberty onset, mainly due to its positive influence on infant growth rate and childhood overweight prevention. The energy imbalance, macro/micronutrient food content, and dietary patterns may modulate the premature activation of the hypothalamic-pituitary-gonadal axis, inducing precocious activation of puberty. An increase in knowledge on the mechanism whereby nutrients may influence puberty will be useful in providing adequate nutritional recommendations to prevent PP and related complications.

Gonadorelins adherence in prostate cancer: A time-series analysis of England's national prescriptions during the COVID-19 pandemic (from Jan 2019 to Oct 2020)

Objective

To examine the effect of the COVID‐19 pandemic on gonadorelin analogue prescription for community patients in England.

Materials and methods

We included data from all primary‐care patients who had relevant prescriptions dispensed in the community in England. Descriptive statistics and interrupted time series analysis over 22 months (15 months before and 7 months after lockdown) was evaluated.

Results

A total of 22 months’ worth of data were analyzed (or 1 041 638 total items, monthly average 47 347 items). Goserelin; leuprorelin, and triptorelin are the medicines most used by total quantity in the study period. Simple descriptive statistics show that mean values have declined during the pandemic. The Interrupted Time Series (ARIMA Modeling) shows declining trends.

After the pandemic's onset, we observe a statistically significant downward trend for goserelin (P = .017) and leuprorelin (P = .014). As these are the major constituents of the model, we interpret this overall data as showing a significant downward category trend. Aside from linearity, a significant step change was noted for leuprorelin (P = .029) showing an increase in prescription items with a similar effect that is close to being statistically significant for goserelin (P = .051).

The actual cost of medicines shows minimal variation suggesting that prices of individual medicines have remained stable. The regional data showed variation but this was not statistically significant. In all cases, the Oct‐20 figures are lower “year on year.” This novel work reports the impact of a global pandemic on prescription volumes of prostate cancer (PCa) medicines.

Conclusions

A worrying decrease in prescription medicines raises concerns for the care of PCa patients. We encourage diagnosed patients to discuss their planned care with their doctor.

Importance of individualizing treatment decisions in girls with central precocious puberty when initiating treatment after age 7 years or continuing beyond a chronological age of 10 years or a bone age of 12 years

OBJECTIVES

Gonadotropin-releasing hormone agonist treatment is important for optimal growth in girls with central precocious puberty (CPP). Data are lacking regarding benefit to height outcome when treatment is started after chronological age (CA) of 7 years, and if continued beyond CA of 10 years or bone age (BA) of 12 years.

METHODS

Forty-eight girls with CPP were treated with monthly leuprolide depot. Change in predicted adult height (PAH) during treatment was assessed. Changes in PAH and growth velocity were compared between girls initiating treatment at CA <7 vs. ≥7 years, and BA ≥12 vs. BA <12 years.

RESULTS

Mean baseline CA was 6.8 years, BA, 10.2 years; and PAH, 156.4 cm. BA/CA ratio decreased from pretreatment values, averaging 1.5 to 1.2 at the end of treatment. Proportion of girls with >5 cm PAH change during treatment was similar, and PAH increased throughout treatment in most girls, regardless of age at treatment initiation. PAH continued to increase in 16/19 girls who continued treatment after BA of 12 years, and also in 16/22 girls who continued treatment after CA of 10 years.

CONCLUSIONS

PAH improved in most girls who initiated treatment after CA of 7 years. It continued to improve in most girls with longer treatment, even past BA of 12 years or CA of 10 years, which suggests that no absolute CA or BA limit should define initiation or end of treatment. Treatment plans need to be individualized, and neither treatment initiation nor cessation should be based on BA or CA alone.

Treatment of Short Stature with Aromatase Inhibitors: A Systematic Review and Meta-Analysis

The objective of the study is to determine the risks and benefits of treating idiopathic short stature (ISS) with aromatase inhibitors (AIs). We comprehensively searched PubMed, Embase, and the China National Knowledge Infrastructure between establishment year and January 31, 2020. Mean difference (MD)/Standardized mean differences (SMD) with 95% confidence intervals (CI) of individual studies were pooled using fixed or random effects models. Subgroup and sensitivity analyses were also performed. Publication bias was estimated using funnel plots and Egger tests. Fourteen studies including 388 participants were included. The meta-analysis results showed that AIs significantly increased final height (MD=2.46, 95% CI: 0.8-4.12) and predicted adult height (MD=0.34, 95% CI: 0.11-0.57). Changes in bone age (MD=-0.1, 95% CI: -0.86-0.66) and bone mineral density (MD=-0.05, 95% CI: -0.19-0.1) were not different between intervention and control group. AI significantly increased testosterone level (SMD=2.01, 95% CI: 0.8-3.23) and reduced estradiol level (SMD=-1.13, 95% CI: -1.87 to -0.40); The intervention and control group had no significant differences in the levels of high-density lipoprotein-cholesterol (SMD=-0.31, 95%CI: -0.68-0.06) and IGF-1 (SMD=0.7, 95% CI: -0.66-2.06) levels. Adverse events were more frequent in the intervention group than in the control group (odds ratio=3.12, 95% CI: 1.44-6.73). In conclusion, both AI monotherapy and AI combination therapy can increase predicted adult height and testosterone levels.

Is surgery effective for treating hypothalamic hamartoma causing isolated central precocious puberty? A systematic review

The aim of this review was to determine the role of surgery in treating hypothalamic hamartoma (HH) causing isolated central precocious puberty (CPP). Literature review was done according to Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. Patients with isolated CPP due to HH, managed with surgical resection, were included. We found 33 studies, reporting 103 patients (76 pedunculated, 27 sessile). Patients were considered "cured" if the symptoms of PP had regressed and the hormone profile had normalized after surgery. Indications for surgery included hamartoma deemed surgically resectable (n-12), for the purpose of tissue diagnosis (n-3), partial response/failure of preoperative therapy (n-9), and unable to afford/to avoid long-term medical therapy (n-7). The extent of resection was total (TR) (n-39), near total/subtotal (NTR/STR) (n-20), partial (PR) (n-35), or unspecified (n-9). On follow-up (range: 3 months-16 years), 73.6% (56/76) of patients with pedunculated HH were cured, while 17.1% (13/76) had partial relief. Only 3/27 (11.1%) of patients with sessile HH were cured. All patients with a pedunculated hamartoma who underwent TR (n=36) improved, with 88.88% cured of the symptoms. Surgery had no effect in 17/23 (73.9%) patients with sessile HH who underwent PR. Psychological symptoms improved in 10/11 patients. There was no mortality. Permanent complications, in the form of 3rd nerve palsy, occurred in 3.7% (2/54) of the patients. To conclude, in the current era of availability of GnRH analogs, surgical resection in a subset of patients may be acceptable especially for small pedunculated hamartomas.

Growth, bone maturation and ovarian size in girls with early and fast puberty (EFP) and effects of three years treatment with GnRH analogue (GnRHa)

INTRODUCTION

Early puberty (EP) in girls is defined as the onset of thelarche that begins after 6 years and before 8 years and/or acceleration in the tempo of pubertal development. The stage of puberty and the ovarian volume at presentation and the effect of treatment with GnRH analogue (GnRHa) on final adult height are still debated.

PATIENTS AND METHODS

We analyzed the data of 22 girls, who presented early and fast puberty (FEP). The clinical stage of puberty, hormonal levels and the ovarian volume (OV) (measured by ovarian ultra-sonography) at presentation were studied. We recorded the effects of 3 years treatment with GnRHa on their growth in relation to their mid parental height, pubertal progression, and bone maturation.

RESULTS AND CONCLUSION

GnRHa therapy decreased the fast progress of puberty, skeletal maturation, and GV/year. It was successful in increasing the predicted final adult height comparable to or surpassing their mid-parenteral height. A larger OV at presentation was associated with reduced Ht-SDS after 3 years of GnRHa treatment. Clearly, a definitive evaluation of the efficacy of GnRHa as treatment for EFP in girls will require expanded and concerted studies.

Study on the Mechanism of Sarsasapogenin in Treating Precocious Puberty by Regulating the HPG Axis

The present study aims to investigate the effects and mechanisms of sarsasapogenin resistance to precocious puberty. Female Sprague Dawley rats were divided into a normal (N) group, model (M) group, leuprolide (L) group, and sarsasapogenin (Sar) group. Rats at 5 days of age were given a single subcutaneous injection of 300 micrograms of danazol to establish the precocious puberty model. After 10 days of modeling, drug intervention was started. The development of the uterus and ovary was observed by hematoxylin and eosin (HE) staining. The levels of the serum luteinizing hormone (LH), follicle-stimulating hormone (FSH), and estradiol (E2) were determined by radioimmunoassay. Also, the expressions of the hypothalamic gonadotropin releasing hormone (GnRH), Kiss-1, G protein-coupled receptor 54 (GPR54), and pituitary gonadotropin releasing hormone receptor (GnRH-R) were detected by RT-PCR. The results showed that compared with the model group, sarsasapogenin could significantly delay the opening time of vaginal, decreased uterine and ovarian coefficients, and reduced uterine wall thickness. Moreover, it can significantly downregulate the levels of serum hormones and reduce the expression of GnRH, GnRH-R, and kiss-1. In summary, our results indicate that sarsasapogenin can regulate the HPG axis through the kiss-1/GPR54 system for therapeutic precocious puberty.

Adult height after gonadotropin-releasing hormone agonist treatment in girls with early puberty: A meta-analysis

OBJECTIVE

This analysis of previously published reports was performed to examine the effects of gonadotropin-releasing hormone (GnRH) agonist treatment on adult height and the factors associated with adult height outcomes.

CONTEXT

GnRH agonists are first-line agents in the treatment of precocious puberty. However, studies regarding the treatment effect on subjects with early puberty have reported inconsistent results.

DESIGN

A total of 14 studies identified from a search of electronic databases (AMED, EMBASE, MEDLINE and RISS) were included. Controlled studies with girls who developed puberty before 10 years of age and measurements of the adult heights of the subjects were selected. Studies using only long-acting GnRH agonists to suppress puberty were included. Adult height, duration of the treatment, age at the start of treatment and bone age advancement were analysed.

RESULTS

The mean age of the subjects ranged from 6.3 to 9.0 years. The meta-analysis showed a pooled mean difference in adult height of 3.2 cm and a 95% confidence interval of 1.3-5.1 cm. The height difference between the treated subjects and controls was significantly associated with the duration of treatment (P = .005) rather than the age at the start of treatment (P = .084) or the difference between bone age and chronological age (P = .427).

CONCLUSIONS

Administration of GnRH agonists in girls who develop early puberty and demonstrate advanced bone age may be effective for increasing adult height, especially if a sufficiently long treatment duration can be achieved.

The Influence of Gonadotropin-Releasing Hormone Agonist Treatment on Thyroid Function Tests in Children with Central Idiopathic Precocious Puberty

Introduction:

In recent years, the treatment of idiopathic central precocious puberty using gonadotropin-releasing hormone agonist (GnRH) agonist has been considered as a common treatment. To date, there is not much information about the effect of GnRH agonist treatment on pediatric thyroid function.

Aim:

The aim of this study was to evaluate the influence of GnRH treatment on thyroid function tests in children with central idiopathic precocious puberty.

Material and Methods:

This cross-sectional study investigated 50 children with idiopathic precocious puberty treated with GnRH agonist, who were referred to Bahrami pediatric hospital, Tehran, Iran. Patients` height, weight, and symptoms of hypothyroidism were evaluated every two months. Thyroid function tests, T4 and thyroid-stimulating hormone (TSH), were reviewed every 6 months. Data were analyzed using SPSS Statistics, Version 18.

Results:

The majority of the children who participate in this study were female. 72% of children with central idiopathic precocious puberty had a significant increase in TSH level (P=0.002). In this group of patients, 66% and 6% had subclinical and clinical increases in thyroid function tests, respectively. The estimated time to thyroid dysfunction was 12.37 months. It is found that only 2% of patients showed thyroid dysfunction during the first 6 months of the treatment.

Conclusion:

The results of this study showed that more than 70% of children who were undergoing GnRH agonist treatment for central precocious puberty had impaired thyroid function (especially subclinical hypothyroidism). Therefore, evaluating thyroid function in children with precocious puberty who are under treating with GnRH agonist, would be reasonable; especially one year after initiating the treatment.

The Effects of Gonadotropin-Releasing Hormone Analog and a Combination of Gonadotropin-Releasing Hormone Analog and Recombinant Human Growth Hormone on Adult Height in Girls with Early Puberty

Background:

Early puberty (EP) is due to the activation of gonadotropin-releasing hormone (GnRH) pulse generator in lower ages; EP may be a potential cause for impairment of adult height, leading to short stature. The aim of this study was to determine the effects of GnRH analog (GnRHa) and GnRHa plus recombinant human growth hormone (rhGH) treatment on final height in healthy girls with EP.

Materials and Methods:

Fifty EP girls (sexual maturity rating: 2–3) with chronological age (CA) 9.22 ± 0.56 and bone age (BA) 9.74 ± 0.59 years were treated with GnRHa (Triptorelin) at a dose of 100 μg/kg body weight (BW) as intramuscular every 28 days for 2.82 ± 0.57 years; 45 EP girls with CA 9.84 ± 0.57 and BA 10.14 ± 1.02 years were also treated with the same GnRHa plus rhGH (Norditropin) at a dose of 0.1 unit/kg BW daily for 6 days in a week for 2.55 ± 0.6 years. In the control group, 33 EP girls followed for the same period without treatment. Height, weight, and body mass index of girls and parents were assessed. Predicted adult height (PAH) at the start and the end of the study and target height were assessed.

Results:

PAH at the end of the study in the GnRHa group was not different with untreated girls. PAH at the end of the treatment in GnRHa plus rhGH group was significantly higher than both untreated and GnRHa group. PAH at the end of therapy in GnRHa plus rhGH group was significantly more than their target height.

Conclusion:

GnRHa therapy has a benefit effect in achievement of target height. Combination therapy with GnRHa plus rhGH increased their PAH more than both untreated and GnRHa groups.

COMPARATIVE EFFICACY AND SAFETY OF THREE CURRENT CLINICAL TREATMENTS FOR GIRLS WITH CENTRAL PRECOCIOUS PUBERTY: A NETWORK META-ANALYSIS

Objective: The optimal treatment for girls with central precocious puberty (CPP) is unknown. We conducted a network meta-analysis to evaluate the efficacy and safety of existing treatments to provide credible clinical guidelines. Methods: We compared gonadotropin-releasing hormone analogue (GnRHa) therapy, GnRHa plus growth hormone (GH) combination therapy, and no-treatment therapy for girls with CPP by performing an electronic search for studies in PubMed, Embase, Chinese National Knowledge Infrastructure databases, and Wanfang Data from their inception until September 30, 2018. Six outcomes, including bone maturation ratio, final height, final height compared with target height, growth velocity, height gain, and gain in predicted adult height (ΔPAH), were expressed as the mean difference with 95% confidence interval. The surface under the cumulative ranking curve (SUCRA) value illustrated the rank probability of each treatment under different outcomes. Results: Twenty-two studies with 1,268 patients were included. GnRHa plus GH had the best performance on final height, final height compared with target height, growth velocity, height gain, and ΔPAH, with the highest SUCRA values of 0.919, 0.975, 0.909, 0.999, and 0.957, respectively. For bone maturation ratio, GnRHa ranked the highest, with a SUCRA value of 0.663. No severe adverse effects were reported. Conclusion: For girls with CPP, GnRHa plus GH had the highest probability of being the optimal therapy for improving final height, and no severe adverse effects were reported. Abbreviations: BMI = body mass index; CI = confidence interval; CPP = central precocious puberty; GH = growth hormone; GnRHa = gonadotropin-releasing hormone analogue; HPG = hypothalamic-pituitary-gonadal; LH = luteinizing hormone; NMA = network meta-analysis; PAH = predicted adult height; PCOS = polycystic ovary syndrome; RCT = randomized controlled trial; SUCRA = surface under the cumulative ranking curve.

Central precocious puberty in girls: Diagnostic study and auxological response to triptorelin treatment

INTRODUCTION

There are several controversies regarding the diagnostic tests and management of central precocious puberty (CPP). The aim of this study is to present the experience acquired in a group of girls with CPP treated with triptorelin, and to analyze the auxological characteristics and diagnostic tests.

MATERIAL AND METHODS

An observational, retrospective study in a group of 60 girls with CPP was conducted between January 2010 and December 2017. Sociodemographic, auxological and hormonal data were recorded at diagnosis, and pelvic ultrasound and magnetic resonance imaging of the head were performed. Girls were treated with triptorelin and monitored after treatment discontinuation until menarche.

RESULTS

At treatment start, chronological age and bone age were 7.7±0.7 and 9.7±0.8 years respectively, and growth velocity was 8.3±1.6cm/year. Target height was 161.1±5.8cm. Peak LH level after stimulation was 16.6±12.1 IU/l. Ovarian volumes were greater than 3mL in 35% of cases. MRI of the head was pathological in seven girls (11.7%). At treatment completion, chronological age and bone age were 10.3±1.1 and 11.2±0.8 years respectively, and growth velocity was 4.7±1.4cm/year. At the age of menarche (11.9±0.9 years), height was 157.5±5.7cm.

CONCLUSIONS

Treatment of CPP with triptorelin appears to be beneficial. The possibility to block pubertal development and slow skeletal maturation allows patients to reach their target height. However, individualized auxological monitoring would be mandatory.

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.

Effect of gestational exposure to arsenic on puberty in offspring female mice

We examined the vaginal opening day, ovary and uterus organ coefficient, reproductive hormone levels of luteinizing hormone (LH) and follicle stimulating hormone (FSH), mRNA and protein expression levels of kiss-1, hypothalamus gonadotrophin releasing hormone 1 (GnRH1), organic cation transporters 2 (Oct2) and transcription termination factor 1 (Ttf1) in different pubertal ages [late lactation (18 days), pre-puberty (21-22 days), puberty (23-27 days; with respect to vaginal opening) and maturity (65 days)] of offspring females, to evaluate the effect of arsenic (As) on puberty initiation after maternal exposure to As at different concentration [0, 0.15, 1.5 and 15 mg/L As(III)] during gestational period. The results showed that the vaginal opening time was significantly advanced in utero in mice exposed to As compared to the control. The hormone level of LH was significantly increased in the mice treated with 15 mg/L of As(III) at puberty compared to the control. During puberty, the mRNA expression levels of kiss-1, GnRH1, Oct2 and Ttf1 in the hypothalamus were significantly increased in the group treated with 15 mg/L of As(III) compared to the control. The protein expressions of Kisspeptin, GnRH1, Oct2 and Ttf1 in the hypothalamus were significantly increased in the pubertal females, while Oct2 and Ttf1 expression levels were significantly decreased in the matured females compared to the control, which is in line with the transcriptional changes of related mRNA expressions. In brief, this study demonstrated that maternal exposure to As during gestational period could result in early onset of puberty in offspring females.

GnRH in the Human Female Reproductive Axis

Gonadotropin-releasing hormone (GnRH) is recognized as the central regulator of the functions of the pituitary-gonadal axis. The increasing knowledge on the mechanisms controlling the development and the function of GnRH-producing neurons is leading to a better diagnostic and therapeutic approach for hypogonadotropic hypogonadisms and for alterations of the puberty onset. During female life span, the function of the GnRH pulse generator may be affected by a number of inputs from other neuronal systems, offering alternative strategies for diagnostic and therapeutic interventions. Moreover, the identification of a GnRH/GnRH receptor system in both human ovary and endometrium has widened the spectrum of action of the peptide outside its hypothalamic functions. The pharmacological use of GnRH itself or its synthetic analogs (agonists and antagonists) provides a valid tool to either stimulate or block gonadotropin secretion and to modulate the female fertility in several reproductive disorders and in assisted reproduction technology. The use of GnRH agonists in young female patients undergoing chemotherapy is also considered a promising therapeutic approach to counteract iatrogenic ovarian failure.

Is a Combination of a GnRH Agonist and Recombinant Growth Hormone an Effective Treatment to Increase the Final Adult Height of Girls with Precocious or Early Puberty?

The aim of treatment for idiopathic central precocious puberty (ICPP) is to increase final adult stature, for which gonadotropin-releasing hormone agonist (GnRHa) is the gold standard. Early puberty is frequently similar to ICPP, with pubertal onset only slightly advanced. Short stature may result from early pubertal onset. Some studies have suggested that recombinant human growth hormone (rhGH) should be combined with a GnRHa to improve adult height, while others have not. Here, the aim was to compare the efficacy of combined GnRHa and rhGH treatment with GnRHa or rhGH treatment alone, or no therapy, for the improvement of the final height of girls with ICPP or early puberty. Electronic databases of randomized and quasi-randomized controlled trials, in which the efficacy of GnRHa preparations was compared with that of rhGH for the treatment of children with precocious or early puberty, were searched and a meta-analysis conducted. Five studies of early puberty and four studies of ICPP were identified. There were no statistically significant differences between final adult height standard deviation score and initial height standard deviation score in the treatment of early puberty (GnRHa and rhGH versus rhGH alone or no treatment). The overall analysis of the data failed to indicate any benefit of combined therapy, while individual reports suggested that in specific instances combined therapy may be beneficial in preserving or reclaiming growth potential and improving adult height.

GnRH agonist treatment for idiopathic central precocious puberty can improve final adult height in Chinese girls

Object

To study the outcomes of GnRHa on final adult height in Chinese idiopathic central precocious puberty (ICPP) girls and the involved factor(s) that can predict height gain.

Methods

We conducted a retrospective analysis on 10 years of data obtained from three clinical hospitals from January 2005 to March 2015, and 101 girls with ICPP, who received GnRHa therapy for more than six months and already reached their adult height were enrolled.

Results

Height, bone age, midparent height, HtSDS, sexual development, therapy duration and predicted adult height(PAH)at start and end of GnRHa, and the final adult height(FAH) were recorded and calculated. Their PAH significantly increased at end of GnRHa (158.4±6.00cm), compared to that at the start of GnRHa(153.1±5.37cm) (P<0.001), and their final adult height(157.0±4.82) significantly increased compared to PAH at start of GnRHa(P<0.001). There was no difference between PAH at end of GnRHa and FAH(P>0.05). After GnRHa therapy, most of the ICPP girls reached their midparent height compared to that at start of GnRHa(P<0.01). FAH was positively correlated with Ht at start, and end of GnRHa, PAH at start and end of GnRHa, and also with midparent height (R²=0.59, 0.74, 0.68, 0.73 and 0.80, P<0.001). While FAH was not correlated with the duration of treatment and BA at start of GnRHa(R² = 0.15and 0.1, P>0.05). The percentage of adult short stature decreased and those reached midparent height significantly increased after GnRHa therapy, compared to that at start of GnRHa(60.6% vs.30.4% and 67.85% vs. 94.64%, respectively, P<0.05).

Conclusions

GnRHa therapy to ICPP girls can effectively achieve the final adult height. After GnRHa therapy, most of these patients reached their midparent height, while few of these patients had an adult short stature.

Characteristics of traditional Chinese medicine usage in children with precocious puberty: A nationwide population-based study

ETHNOPHARMACOLOGICAL RELEVANCE

Precocious puberty (PP) occurs in children with the early onset of pubertal development leading to physical and psychological problems. Current medical treatment is expensive and has its side effects. However, little is known about the utilization of traditional Chinese medicine (TCM) among patients with PP. To characterize the application of TCM among these patients, we conducted a nationwide population-based study.

MATERIALS AND METHODS

We used the Taiwanese National Health Insurance Research Database (NHIRD), to perform a nationwide population-based study. The NHIRD has a derived dataset with the information for a randomly selected half of all insured children from 1997 to 2008 in Taiwan. We identified children <18 years of age with newly diagnosed sexual precocity (ICD-9 CM code: 259.1). The subjects were categorized based on the inclusion of TCM in their treatment plan.

RESULTS

Overall, 3495 newly diagnosed subjects with sexual precocity were included. Among these children, 1.86% (N=65) had used TCM. There were significantly more subjects with no treatment, 87.32% (N=3052), than those with treatment of TCM, western medicine, or both. Most of the TCM users received Chinese herbal remedies (98.25%), and only 1.75% received acupuncture or manipulative therapies. Zhi-Bai-Di-Huang-Wan was the most frequently prescribed TCM formulation (23.73%), while Mai-Ya (Fructus Hordei Germinatus) was the most commonly prescribed single herb (10.87%).

CONCLUSION

Our study identified the characteristics and prescription patterns of TCM for children with PP in Taiwan. Further basic mechanistic studies and clinical trials are needed to confirm the efficacy and mechanism.

Adult height after spontaneous pubertal growth or GnRH analog treatment in girls with early puberty: a meta-analysis

Early puberty (EP) has been defined as the onset of puberty in the low-normal range; it may be a cause for concern regarding a possible impairment of adult height (AH). This paper meta-analysed data on AH after spontaneous growth or after gonadotropin-releasing hormone (GnRH) analog treatment in girls with EP. A computerized literature search was conducted from 1980 to June 30, 2016. Only published studies in English were considered. Eight papers were selected (483 cases). In untreated girls (n = 300), predicted adult height (PAH) at start of follow-up (-0.559 SDS (95%CI -1.110 to 0.001); P = 0.050) was close to mid-parental height (MPH) (-0.557 SDS (95%CI -0.736 to -0.419); P < 0.0001) and AH (-0.663 SDS (95%CI -0.803 to -0.524); P < 0.0001). In GnRH analog treated girls (n = 183), PAH before the start of treatment was slightly reduced (-0.939 SDS (95%CI -1.401 to -0.477; P < 0.0001) vs MPH (-0.678 SDS (95%CI -0.942 to -0.414); P < 0.0000), but AH (-0.604 SDS (95%CI -0.877 to -0.338); P < 0.0000) was close to MPH.

CONCLUSION

Present meta-analysis indicates that girls with EP spontaneously reach their MPH and that GnRH analog treatment does not widely change growth outcome. Differences among the selected studies for definition of EP, inclusion criteria, treatment duration, age at discontinuation of therapy, definition of AH may affect results. What is Known: • Early puberty represents a main cause of consultation in paediatric endocrinology offices due to concerns of both practitioners and parents. • Treatment with GnRH analogs is sometimes attempted with the aim to improve adult height. What is New: • Untreated and GnRH analog treated girls with early puberty reached similar adult height. • Adult height was consistent with mid-parental height in both untreated and GnRH analog treated girls with early puberty.

Effects and safety of combination therapy with gonadotropin-releasing hormone analogue and growth hormone in girls with idiopathic central precocious puberty: a meta-analysis

PURPOSE

This meta-analysis is to evaluate the effects and safety of the combination therapy for girls with idiopathic central precocious puberty (ICPP).

METHODS

Electronic databases were searched for randomized controlled trials (RCTs) and clinical controlled trials (CCTs) that adopted gonadotropin-releasing hormone analogue (GnRHa) therapy and GnRHa plus growth hormone (GH) combination therapy to treat ICPP girls.

RESULTS

A total of six RCTs (162 patients) and six CCTs (247 patients) were included. Compared to the GnRHa therapy group, the combination therapy group achieved taller final height (mean difference, MD = 2.81 cm, 95 % CI 1.76-3.87, four CCTs; MD = 4.30 cm, 95 % CI 0.59-8.01, one RCT); greater progression of final height compared with target height (MD = 3.92 cm, 95 % CI 3.12-4.73, four CCTs; MD = 4.00 cm, 95 % CI 1.93-6.07, One RCT) and larger height gains (MD = 3.49 cm, 95 % CI 0.97-6.01, four CCTs; MD = 3.88 cm, 95 % CI 0.15-7.61, one RCT). No severe adverse effects of treatment were reported.

CONCLUSION

For ICPP girls, the GnRHa and GH combination therapy had advantages over GnRHa alone on final height and no severe adverse effects were reported. We recommend comprehensive assessment of the individual growth rate, patient compliance, the clinical effects, the height expectations of individual patients and the treatment cost to the family in order to identify the best therapy for individual patients.

The Efficacy of GnRHa Alone or in Combination with rhGH for the Treatment of Chinese Children with Central Precocious Puberty

The addition of recombinant human growth hormone (rhGH) to GnRH agonist (GnRHa) to treat central precocious puberty (CPP) is controversial. We systemically reviewed and evaluated the efficacy and safety of the rhGH and GnRHa adjunctive therapy in Chinese children with CPP and assessed the influence of age and therapy duration on the efficacy of the combined treatment. A total of 464 patients were included from 14 studies. Compared with baseline, administration of GnRHa plus rhGH led to a significant increase in height, predicted adult height (PAH) and height standard deviation for bone age (HtSDS-BA), corresponding to a weighted mean difference (WMD) (95%CI) of 9.06 cm (6.41, 11.70), 6.5 cm (4.47, 8.52), and 0.86 (0.58, 1.14) respectively. Subgroup analysis showed the combined therapy had increased efficacy in subjects with initial treatment age younger than 10 years old or with treatment lasting over 12 months. Compared with GnRHa alone treatment, the combined treatment led to a significant increase in height, PAH and HtSDS-BA, corresponding to a WMD (95% CI) of 3.56 cm (2.54, 4.57), 3.76 cm (3.19, 4.34) and 0.56 (0.43, 0.69). The combined treatment exhibited no safety concerns. Our findings may aid clinicians in making treatment decisions for children with CPP.

GnRH and GnRH receptors in the pathophysiology of the human female reproductive system

BACKGROUND

Human reproduction depends on an intact hypothalamic-pituitary-gonadal (HPG) axis. Hypothalamic gonadotrophin-releasing hormone (GnRH) has been recognized, since its identification in 1971, as the central regulator of the production and release of the pituitary gonadotrophins that, in turn, regulate the gonadal functions and the production of sex steroids. The characteristic peculiar development, distribution and episodic activity of GnRH-producing neurons have solicited an interdisciplinary interest on the etiopathogenesis of several reproductive diseases. The more recent identification of a GnRH/GnRH receptor (GnRHR) system in both the human endometrium and ovary has widened the spectrum of action of the peptide and of its analogues beyond its hypothalamic function.

METHODS

An analysis of research and review articles published in international journals until June 2015 has been carried out to comprehensively summarize both the well established and the most recent knowledge on the physiopathology of the GnRH system in the central and peripheral control of female reproductive functions and diseases.

RESULTS

This review focuses on the role of GnRH neurons in the control of the reproductive axis. New knowledge is accumulating on the genetic programme that drives GnRH neuron development to ameliorate the diagnosis and treatment of GnRH deficiency and consequent delayed or absent puberty. Moreover, a better understanding of the mechanisms controlling the episodic release of GnRH during the onset of puberty and the ovulatory cycle has enabled the pharmacological use of GnRH itself or its synthetic analogues (agonists and antagonists) to either stimulate or to block the gonadotrophin secretion and modulate the functions of the reproductive axis in several reproductive diseases and in assisted reproduction technology. Several inputs from other neuronal populations, as well as metabolic, somatic and age-related signals, may greatly affect the functions of the GnRH pulse generator during the female lifespan; their modulation may offer new possible strategies for diagnostic and therapeutic interventions. A GnRH/GnRHR system is also expressed in female reproductive tissues (e.g. endometrium and ovary), both in normal and pathological conditions. The expression of this system in the human endometrium and ovary supports its physiological regulatory role in the processes of trophoblast invasion of the maternal endometrium and embryo implantation as well as of follicular development and corpus luteum functions. The GnRH/GnRHR system that is expressed in diseased tissues of the female reproductive tract (both benign and malignant) is at present considered an effective molecular target for the development of novel therapeutic approaches for these pathologies. GnRH agonists are also considered as a promising therapeutic approach to counteract ovarian failure in young female patients undergoing chemotherapy.

CONCLUSIONS

Increasing knowledge about the regulation of GnRH pulsatile release, as well as the therapeutic use of its analogues, offers interesting new perspectives in the diagnosis, treatment and outcome of female reproductive disorders, including tumoral and iatrogenic diseases.