Acceleration of luteinizing hormone pulse frequency in adolescent girls with a history of central precocious puberty with versus without hyperandrogenism

Prevalence of Polycystic Ovarian Syndrome in Girls with a History of Idiopathic Central Precocious Puberty

INTRODUCTION

The prevalence of polycystic ovarian syndrome (PCOS) in adolescent girls is between 1 and 4.3%. It remains controversial whether women with a history of idiopathic central precocious puberty (ICPP) are at increased risk for PCOS. Our objective was to assess the prevalence of PCOS in adolescents with a history of ICPP compared with healthy adolescents and the prevalence of PCOS among ICPP girls who have received or not gonadotropin-releasing hormone analogue (GnRHa) treatment.

METHODS

We assessed post-menarcheal girls with a history of ICPP. Girls were evaluated at gynecological age ≥2.5 years. Data collected were age at menarche, menstrual cycle characteristics, BMI, clinical hyperandrogenism (HA), total and free testosterone levels. PCOS diagnosis was defined by criteria for adolescents. Subjects were also analyzed regarding whether or not they had received GnRHa treatment.

RESULTS

Ninety-four subjects were assessed, and 63 had been treated with GnRHa. Menstrual disorders were found in 29%, clinical HA in 36%, and biochemical HA in 23%. Twelve percent met the diagnostic criteria for PCOS. There was no difference in BMI or in the incidence of menstrual dysfunction or hyperandrogenemia between treated and untreated patients. A higher proportion of clinical HA was found in untreated patients when compared to treated girls. The relative risk (RR) of developing PCOS in ICPP girls was 2.5 compared to a population of healthy adolescents. This RR was not higher in patients who received treatment with GnRHa than in those who did not.

CONCLUSION

Adolescent girls with a history of ICPP have an increased risk of PCOS. This risk seems not to be related to GnRHa treatment.

Gonadotropin releasing hormone analogue treatment of central precocious puberty is not associated with altered prevalence of polycystic ovary syndrome: a single center cohort study

Background

There is conflicting evidence regarding an association between gonadotropin releasing hormone analogue (GnRHa) therapy and polycystic ovary syndrome (PCOS). This study aimed to compare the prevalence of endocrine disorders, primarily PCOS, between women who had been treated with GnRHa for central precocious puberty (CPP) and those who were not treated.

Methods

This was a retrospective cohort study, including women diagnosed with central precocious puberty between 1989 and 2011 in a university affiliated tertiary medical center. Data collected included demographic data, medical background, clinical presentation at diagnosis and duration of treatment (zero for non-treated). Gynecologic and endocrine long-term outcomes were compared by treatment group.

Results

Fifty-one women were included in the study, 27/51 had been treated with gonadotropin releasing hormone analogue (GnRHa). Overall prevalence of PCOS was 19.6%. No statistically significant difference in prevalence of PCOS was demonstrated between the treated and non-treated groups. Similarly, overall prevalence of either clinical or laboratory hyper-androgenism, was 29.4% and 33.3%, for the treatment and non-treatment groups respectively (p = non-significant).

Conclusions

GnRHa treatment for precocious puberty is not associated with increased risk of polycystic ovary syndrome.

Diagnostic value of pituitary volume in girls with precocious puberty

BACKGROUND

To date, the gonadotropin-releasing hormone (GnRH) stimulation test is still the gold standard for precocious puberty (PP) diagnosis. However, it has many disadvantages, including low sensitivity, high cost, and invasive operation. This study aims to evaluate whether magnetic resonance imaging (MRI)-derived variables, including pituitary volume (PV), could be used as diagnostic factors for PP in girls, providing a non-invasive diagnostic approach for PP.

METHODS

A total of 288 young female patients who presented to the Clinic of Pediatric Endocrinology for evaluation of PP from January 2015 to December 2017 were enrolled. The sample included 90 girls diagnosed with premature thelarche (PT), 133 girls determined as idiopathic central precocious puberty (ICPP), 35 early pubertal girls, and 30 normal girls. All patients received pituitary MRI examinations.

RESULTS

The largest PV and pituitary height were shown in the ICPP and pubertal groups, followed by the PT group. The receiver operating characteristic (ROC) curve analysis showed that PV is a predictive marker for ICPP, with a sensitivity of 54.10% and a specificity of 72.20% at the cutoff value of 196.01 mm³. By univariate analysis, PV was positively associated with peak luteinizing hormone (LH), LH/follicle-stimulating hormone (FSH), age, bone age, and body mass index (BMI) (all P < 0.05). However, bone age and peak LH were the only significant predictors of PV as demonstrated by the stepwise multivariate regression analysis (Model: PV = 9.431 * bone age + 1.230 * peak LH + 92.625 [P = 0.000, R² = 0.159]).

CONCLUSIONS

The PV in the ICPP group was significantly higher than in PT and control groups, but there was no reliable cutoff value to distinguish ICPP from PT. Pituitary MRI should be combined with clinical and laboratory tests to improve the diagnostic value of PV for PP.

Hyperactive LH Pulses and Elevated Kisspeptin and NKB Gene Expression in the Arcuate Nucleus of a PCOS Mouse Model

Polycystic ovary syndrome (PCOS), a common reproductive disorder in women, is characterized by hyperandrogenemia, chronic anovulation, cystic ovarian follicles, and luteinizing hormone (LH) hyper-pulsatility, but the pathophysiology isn't completely understood. We recently reported a novel mouse model of PCOS using chronic letrozole (LET; aromatase inhibitor). Letrozole-treated females demonstrate multiple PCOS-like phenotypes, including polycystic ovaries, anovulation, and elevated circulating testosterone and LH, assayed in "one-off" measures. However, due to technical limitations, in vivo LH pulsatile secretion, which is elevated in PCOS women, was not previously studied, nor were the possible changes in reproductive neurons. Here, we used recent technical advances to examine in vivo LH pulse dynamics of freely moving LET female mice versus control and ovariectomized (OVX) mice. We also determined whether neural gene expression of important reproductive regulators such as kisspeptin, neurokinin B (NKB), and dynorphin, is altered in LET females. Compared to controls, LET females exhibited very rapid, elevated in vivo LH pulsatility, with increased pulse frequency, amplitude, and basal levels, similar to PCOS women. Letrozole-treated mice also had markedly elevated Kiss1, Tac2, and Pdyn expression and increased Kiss1 neuronal activation in the hypothalamic arcuate nucleus. Notably, the hyperactive LH pulses and increased kisspeptin neuron measures of LET mice were not as elevated as OVX females. Our findings indicate that LET mice, like PCOS women, have markedly elevated LH pulsatility, which likely drives increased androgen secretion. Increased hypothalamic kisspeptin and NKB levels may be fundamental contributors to the hyperactive LH pulse secretion in the LET PCOS-like condition and, perhaps, in PCOS women.

A Novel Letrozole Model Recapitulates Both the Reproductive and Metabolic Phenotypes of Polycystic Ovary Syndrome in Female Mice

Polycystic ovary syndrome (PCOS) pathophysiology is poorly understood, due partly to lack of PCOS animal models fully recapitulating this complex disorder. Recently, a PCOS rat model using letrozole (LET), a nonsteroidal aromatase inhibitor, mimicked multiple PCOS phenotypes, including metabolic features absent in other models. Given the advantages of using genetic and transgenic mouse models, we investigated whether LET produces a similar PCOS phenotype in mice. Pubertal female C57BL/6N mice were treated for 5 wk with LET, which resulted in increased serum testosterone and normal diestrus levels of estradiol, similar to the hyperandrogenemia and follicular phase estrogen levels of PCOS women. As in PCOS, ovaries from LET mice were larger, polycystic, and lacked corpora lutea versus controls. Most LET females were acyclic, and all were infertile. LET females displayed elevated serum LH levels and higher Lhb mRNA in the pituitary. In contrast, serum FSH and Fshb were significantly reduced in LET females, demonstrating differential effects on gonadotropins, as in PCOS. Within the ovary, LET females had higher Cyp17, Cyp19, and Fsh receptor mRNA expression. In the hypothalamus, LET females had higher kisspeptin receptor mRNA expression but lower progesterone receptor mRNA levels. LET females also gained more weight than controls, had increased abdominal adiposity and adipocyte size, elevated adipose inflammatory mRNA levels, and impaired glucose tolerance, mirroring the metabolic phenotype in PCOS women. This is the first report of a LET paradigm in mice that recapitulates both reproductive and metabolic PCOS phenotypes and will be useful to genetically probe the PCOS condition.

Treated and untreated women with idiopathic precocious puberty: long-term follow-up and reproductive outcome between the third and fifth decades

CONTEXT

Central precocious puberty (CPP), treated or untreated, may have implications in adulthood.

OBJECTIVE

To assess the reproductive outcome and social adjustment of former CPP women between the 3rd and 5th decades of life.

DESIGN

Cross-sectional study of an historical cohort.

METHODS

Demographic data and gynaecological history of 214 CPP women aged 25-56 years [135 GnRH analogue (GnRHa)-treated, 18 cyproterone acetate (CyA)-treated, 61 untreated] and of 446 controls with normal puberty, matched for age and year of birth, were recorded in a structured interview.

RESULTS

Marital status, education and number of children were similar in CPP women and controls. Clinical hyperandrogenism (acne/hirsutism with oligomenorrhoea) was more frequently reported in CPP women than in controls: GnRHa-treated 29·6% vs 17·4% (P = 0·006), CyA-treated 50% vs 20·4% (P = 0·04), untreated 34·4% vs 17·2% (P = 0·003), with no significant difference between CPP groups. Spontaneous pregnancy was similarly achieved by treated CPP and controls: GnRHa-treated 90·4% vs 93·4%, CyA-treated 86·7% vs 90·2%. Assisted fertilization rate was higher in untreated CPP than treated CPP groups (P = 0·006) and controls (P = 0·03). Untreated CPP was the only parameter associated with clinical hyperandrogenism (OR=2·04, 95% CI, 1·0-4·16, P = 0·07) and fertility problems (OR=3·40, 95% CI, 1·15-10·0, P = 0·047). Course of pregnancy was uneventful in 90·2% of CPP women and 90·9% of controls.

CONCLUSIONS

The increased rate of clinical hyperandrogenism among CPP women implies that the underlying neuroendocrine dysfunction persists into adult life. Pubertal suppression treatment may have a protective effect as fertility problems were more prevalent only among untreated CPP women. Educational achievements and marital status were unaffected by CPP.

GNRH analog therapy in girls with early puberty is associated with the achievement of predicted final height but also with increased risk of polycystic ovary syndrome

OBJECTIVE

GNRH analog (GNRHa) therapy has not been supported by beneficial effects on adult stature in girls with early puberty. Furthermore, an increased prevalence of polycystic ovary syndrome (PCOS) has been described in girls treated for central precocious puberty. Women with PCOS are at increased risk of cardiometabolic dysfunctions and infertility. Our aim was to assess GNRHa effectiveness on reaching adult stature and the risk of PCOS in girls with early puberty.

DESIGN

Longitudinal study of GNRHa-treated and GNRHa-untreated girls at baseline and at final height.

METHODS

Twenty-five GNRHa-treated girls and 55 controls were compared. Insulin resistance (IR; homeostasis model assessment of IR (HOMA-IR) and glucose-to-insulin ratio (G/I)), the effect of GNRHa on final height, and the prevalence of PCOS were assessed.

RESULTS

In GNRHa-treated girls, no significant difference was found between predicted final height and final height, whereas a significant difference was detected in untreated girls (P=0.0001). At final height, GNRHa-treated girls showed higher HOMA-IR and lower G/I (P=0.03 for both) as well as higher DHEAS and androstenedione levels (P=0.02 and P=0.01 respectively) than untreated girls. The prevalence of PCOS and hyperandrogenemia was significantly higher in GNRHa-treated adolescents than in untreated adolescents (36 and 14.5% respectively, P=0.04; 56 and 23.6% respectively, P=0.01). Finally, gonadotropin-suppressive therapy was significantly related to PCOS during adolescence (P=0.03).

CONCLUSIONS

In girls with early puberty, GNRHa therapy is associated with the achievement of predicted final height; nevertheless, this treatment seems to act as an independent risk factor for the development of PCOS already during adolescence.

Consensus statement on the use of gonadotropin-releasing hormone analogs in children

OBJECTIVE

Gonadotropin-releasing hormone analogs revolutionized the treatment of central precocious puberty. However, questions remain regarding their optimal use in central precocious puberty and other conditions. The Lawson Wilkins Pediatric Endocrine Society and the European Society for Pediatric Endocrinology convened a consensus conference to review the clinical use of gonadotropin-releasing hormone analogs in children and adolescents.

PARTICIPANTS

When selecting the 30 participants, consideration was given to equal representation from North America (United States and Canada) and Europe, an equal male/female ratio, and a balanced spectrum of professional seniority and expertise.

EVIDENCE

Preference was given to articles written in English with long-term outcome data. The US Public Health grading system was used to grade evidence and rate the strength of conclusions. When evidence was insufficient, conclusions were based on expert opinion.

CONSENSUS PROCESS

Participants were put into working groups with assigned topics and specific questions. Written materials were prepared and distributed before the conference, revised on the basis of input during the meeting, and presented to the full assembly for final review. If consensus could not be reached, conclusions were based on majority vote. All participants approved the final statement.

CONCLUSIONS

The efficacy of gonadotropin-releasing hormone analogs in increasing adult height is undisputed only in early-onset (girls <6 years old) central precocious puberty. Other key areas, such as the psychosocial effects of central precocious puberty and their alteration by gonadotropin-releasing hormone analogs, need additional study. Few controlled prospective studies have been performed with gonadotropin-releasing hormone analogs in children, and many conclusions rely in part on collective expert opinion. The conference did not endorse commonly voiced concerns regarding the use of gonadotropin-releasing hormone analogs, such as promotion of weight gain or long-term diminution of bone mineral density. Use of gonadotropin-releasing hormone analogs for conditions other than central precocious puberty requires additional investigation and cannot be suggested routinely.

Prevalence of polycystic ovary syndrome in young women who had idiopathic central precocious puberty

OBJECTIVE

To assess the prevalence of polycystic ovary syndrome (PCOS) in a cohort of young women with previous idiopathic central precocious puberty (ICPP) at least 3 years after menarche, and to look for any predictive factors of PCOS at the time ICPP was diagnosed.

DESIGN

Longitudinal study.

SETTING

Pediatrics unit, Verona, Italy.

PATIENT(S)

Forty-six young women (18.1 +/- 3.0 years) who had been treated with GnRH analogues during childhood, observed at gynecologic age of 6.23 +/- 3.3 years.

INTERVENTION(S)

Semistructured interview concerning cycles, physical exam, blood sampling, and transabdominal pelvic ultrasound.

MAIN OUTCOME MEASURE(S)

Oligomenorrhea, LH, FSH, E(2), T, DHEAS, free T, delta4-androstenedione, 17-OHP, P, polycystic ovary morphology (PCOM).

RESULT(S)

Fifteen percent of the young women had oligomenorrhea, 28% clinical hyperandrogenism, 48% biochemical hyperandrogenism, and 37% PCOM. A total of 32% of the patients had PCOS according to the Rotterdam definition and 30% had PCOS according to the Androgen Exess Society. The prevalent phenotype of PCOS was characterized by clinical and/or biochemical hyperandrogenism and PCOM. We did not find any predictive factors for PCOS at the time ICPP was diagnosed.

CONCLUSION(S)

Patients with ICCP are prone to developing PCOS. The prominent phenotype in this cohort was PCOM associated with clinical and/or biochemical hyperandrogenism. Further follow-ups of these young adult patients will clarify whether this phenotype persists and if it will have important long-term implications regarding increased risk of infertility or metabolic complications.

Endocrine antecedents of polycystic ovary syndrome in fetal and infant prenatally androgenized female rhesus monkeys

Experimentally induced fetal androgen excess induces polycystic ovary syndrome-like traits in adult female rhesus monkeys (Macaca mulatta). Developmental changes leading to this endocrinopathy are not known. We therefore studied 15 time-mated, gravid female rhesus monkeys with known female fetuses. Nine dams received daily s.c. injections of 15 mg of testosterone propionate (TP), and six received injections of oil vehicle (control) from 40 through 80 days of gestation (term, 165 days; range, +/-10 days). All fetuses were delivered by cesarean section using established methods at term. Ultrasound-guided fetal blood sample collection and peripheral venous sample collection of dams and subsequent infants enabled determination of circulating levels of steroid hormones, LH and FSH. The TP injections elevated serum testosterone and androstenedione levels in the dams and prenatally androgenized (PA) fetuses. After cessation of TP injections, testosterone levels returned to values within the reference range for animals in these age groups, whereas serum androstenedione levels in PA infants were elevated. The TP injections did not increase estrogen levels in the dams or the PA fetuses or infants, yet conjugated estrogen levels were elevated in the TP-injected dams. Serum levels of LH and FSH were elevated in late-gestation PA fetuses, and LH levels were elevated in PA infants. These studies suggest that experimentally induced fetal androgen excess increases gonadotropin secretion in PA female fetuses and infants and elevates endogenous androgen levels in PA infants. Thus, in this nonhuman primate model, differential programming of the fetal hypothalamo-pituitary unit with concomitant hyperandrogenism provides evidence to suggest developmental origins of LH and androgen excess in adulthood.