Premature Thelarche–Natural History and Sex Hormone Secretion in 68 Girls

ABSTRACT. Data obtained during long-term follow-up of 68 girls with premature thelarche were analysed. In 85 % onset was before the age of 2 years, in 30.8 % being present at birth. In 44.1 % there was a regression after 3^2/12±2^8/12 12years (SD). Basal levels of plasma FSH and response to LH-RH were significantly higher than prepubertal controls (1.93± 1.56 vs. 0.8±0.1 mU/ml and peaks 12.3±5.4 vs. 7.9±1.0 mU/ml respectively; p <0.001). Twenty-seven of 52 patients tested had increased plasma estradiol and in 27 of 40 patients tested, urocytograms or vaginal smear showed estrogenization. Basal levels of LH and response to LH-RH were prepubertal. The girls with premature thelarche were significantly taller than normal controls of the same age ( p <0.001). These results suggest that premature thelarche is an incomplete form of precocious sexual development probably due to derangement in the maturation of the hypothalamo-pituitary-gonadal axis which results in a higher than normal secretion of FSH, as well as a defect in the peripheral sensitivity to the sex hormones.     

Gonadotrophin response to LH-RH in boys with delayed growth and adolescence.

Plasma luteinising hormone (LH) and follicle-stimulating hormone (FSH) concentrations were measured before and after intravenous luteinising hormone-releasing hormone (LH-RH) in 33 boys with growth delay. Eighteen were prepubertal and 15 pubertal. Basal LH and FSH levels were low in both groups with mean increments after LH-RH of 3.2 +/- 0.8 U/l (mean +/- SEM) and 2.6 +/- 0.4 U/l respectively in the prepubertal and 7.4 +/- 0.7 U/l and 2.0 +/- 0.3 U/l in the pubertal boys. The LH increment showed a positive correlation with increasing bone age (r = 0.71, P less than 0.001); FSH did not. The LH-RH response thus appeared normal in relation to the stage of maturity.     

The significance and characteristics of the LHRH test in diagnosing precocious puberty development in girls: the stimulated LH/FSH quotient differentiates between central precocious puberty and premature thelarche

LHRH tests (100 micrograms i.v.) were performed in 31 girls with central precocious puberty (PP); the girls were participating in an international multicentre trial for the treatment of PP with the LHRH agonist decapeptyl in microspheres, together with 18 girls with premature thelarche (PT). Assignment to these two groups was made after 6 months to 5 years of clinical follow-up. LH and FSH were determined centrally using a polyclonal RIA. Basal LH and FSH levels and stimulated LH levels were significantly higher in PP patients (p less than 0.001), but the stimulated FSH levels were not significantly different between the two groups. In the PP group, all stimulated LH levels were above the prepubertal range, whereas in the PT patients all stimulated LH levels were within the prepubertal reference limits. In PP and PT patients 52% and 56%, respectively, of the stimulated FSH levels were increased above the range for prepubertal girls. In 55% of the PP patients, stimulated LH levels were also above the reference range for the corresponding Tanner breast stage. In contrast, all stimulated LH levels of the PT group were within the reference limits for their breast stage. For FSH, 45% and 56% of the stimulated levels were above the normal ranges for the corresponding breast stages in the PP and PT groups, respectively. The LH-to-FSH ratio after LHRH stimulation was significantly higher in the PP than in the PT group (p less than 0.001). All but one of these ratios were above 1 in the PP patients and all ratios in the PT patients were below 1.(ABSTRACT TRUNCATED AT 250 WORDS)     

Serum insulin-like growth factor (IGF)-I and IGF-binding protein-3 in girls with premature thelarche

Premature thelarche (PT) is characterised by precocious breast development without any other sign of puberty, normal height velocity (HV) and normal bone maturation, while girls with central precocious puberty (CPP) show increased HV, bone maturation and increased serum IGF-I and IGFBP-3 levels. This prompted us to study serum IGF-I and IGFBP-3 concentrations in girls with PT. Thirty-nine girls with premature breast development were studied and classified as PT or CPP according to clinical and laboratory evaluation. Normal prepubertal and pubertal girls were studied as controls. Serum IGF-I and IGFBP-3 were determined in all girls by IRMA. IGF-I levels in PT (155 +/- 61 microg/l) were lower than in CPP (337 +/- 149 microg/l) or late-pubertal controls (355 +/- 84 microg/l) and similar to those found in prepubertal (113 +/- 72 microg/l) and early-pubertal (222 +/- 81 microg/l) girls. Considering the SDS of IGF-I for chronological age (CA), the values observed in PT were in an intermediate position between CPP and prepubertal controls and statistically similar to those observed in CPP and prepubertal girls. IGFBP-3 levels in PT (2.1 +/- 0.5 mg/l) were similar to those found in CPP (2.5 +/- 0.8 mg/l), but only the latter were higher than in prepubertal girls (1.9 +/- 0.9 mg/l). IGF-I/IGFBP-3 molar ratios in PT were in an intermediate position between CPP and prepubertal controls. In conclusion, IGF-I and IGF-I/IGFBP-3 values in PT are intermediate between those observed in prepubertal children and in CPP, suggesting that PT could be a very early stage of puberty with slight but real changes in the GH-IGF axis.     

Breast contact thermography for differentiation between premature thelarche and true precocious puberty

Breast contact thermography was used to differentiate between premature thelarche and true precocious puberty. The technique was applied to 10 girls with premature thelarche, 12 with precocious puberty and 105 controls (Tanner B1-5). In controls, the scores attributed to the maturative thermographic signs correlated with breast development stages. In premature thelarche thermographic signs of vascularization were always absent, while in precocious puberty they were always observed, although in some cases unilaterally. The thermographic index (higher total score between the two breasts) ranged from 0 to 3 in girls with premature thelarche and from 4 to 10 in girls with precocious puberty. The thermographic pattern in premature thelarche was similar to that in prepubertal girls and did not progress in two girls who were repeatedly examined. We emphasize the useful role of contact thermography in evaluating pubertal breast development and in differentiating between premature thelarche and true precocious puberty.Abbreviations BCT breast contact thermography - TI thermographic index - B breast development stage - F fundus - N nipple - A areolar zone - V vascular growth pattern     

A comparison of patients with premature thelarche and idiopathic true precocious puberty in the initial stage of illness

A comparative study of patients with premature thelarche and patients with idiopathic true precocious puberty was conducted. The age at the first visit tended to be lower for those with precocious puberty. In comparison with normative data for children, the frequency of low birthweight and small for date (SFD) status was greater in the 55 patients with premature thelarche, but SFD was also frequent in the 18 patients with precocious puberty. The height, weight and Kaup's index were all within the normal range for these two groups. The ratios for bone age/chronologic age and bone age/height age tended to be high in both groups. In the patients with premature thelarche, the blood luteinizing hormone (LH) level showed a normal response, and the blood follicle stimulating hormone (FSH) level a hyper-response, to stimulation with luteinizing hormone-releasing hormone (LH-RH). In contrast, both the blood LH and FSH levels showed a normal response to LH-RH stimulation in most of the patients with precocious puberty, and a hyper-response was rare among them. Although the blood estradiol (E2) level was higher in patients with precocious puberty than in those with premature thelarche, about 50% and 90% of the patients in the respective groups had normal levels. These results suggest that normal responses of blood LH and excessive responses of blood FSH to LH-RH loading may be useful in some patients for diagnosing premature thelarche at an early stage.     

Serum leptin levels in premature pubarche and prepubertal girls with and without obesity

Leptin can be regarded as a marker of the nutritional status of the body. This study was performed to determine the correlation of leptin levels with insulin (I) and androgens in girls with premature pubarche (PP) and prepubertal controls (C) with (OB) or without (nOB) obesity. We studied 25 girls with PP and 14 C; girls were dived into two subgroups according to body mass index (BMI): OB (18 PP and 8 C) and nOB (7 PP and 6 C). Obesity was defined as BMI >95th percentile for chronological age. Serum levels of leptin, I, glucose (G), DHEAS, testosterone, androstenedione (A), cortisol, SHBG, IGFBP-1 and lipid profile were measured. The fasting G to I ratio (FGIR) was calculated and FGIR <7 was considered as suggestive of I resistance (IR). Data were analyzed comparing PP vs C and OB vs nOB. Serum DHEAS (0.60 +/- 0.45 vs 0.18 +/- 0.22 microg/ml) and A (895.5 +/- 420.4 vs 457.0 +/- 352.1 pg/ml) levels were significantly higher in PP than C. Other hormonal and metabolic parameters were similar. Serum leptin (30.8 +/- 18.3 vs 8.1 +/- 5.9 ng/ml), A (841.8 +/- 471.1 vs 522.5 +/- 317.2 pg/ml), DHEAS (0.53 +/- 0.44 vs 0.31 +/- 0.39 microg/ml), G (88.4 +/- 8.8 vs 80.2 +/- 8.1 mg/dl), I (13.5 +/- 7.7 vs 5.1 +/- 3.7 microU/ml) and total cholesterol (TC) (180.5 +/- 30.9 vs 161.8 +/- 29.5 mg/dl) levels were greater in the OB than in the nOB group. IR was observed in 10 girls with OB and in one with nOB. Leptin was correlated with BMI (r = 0.83), SHBG (r = -0.44), IGFBP-1 (r = -0.47), I (r = 0.37), A (r = 0.48) and TC (r = 0.36), but in multiple regression analysis only with BMI (r2 = 0.72, p < 0.001). Girls with PP and prepubertal OB girls showed elevated leptin levels independent of I and androgen levels. Girls with OB had a greater degree of hyperandrogenism and IR. As obesity, IR and hyperandrogenism are common findings in polycystic ovary syndrome (PCOS), which is more prevalent in young women with a history of PP, a role of leptin in PCOS can be suggested. In addition, girls with PP could be considered a population at risk for plurimetabolic syndrome.     

Effect of synthetic luteinizing hormone-releasing hormone on the release of gonadotropins in hypophysogonadal disorders of children and adolscents. VII. Constitutional delay of puberty in males.

Serum gonadotropins (LH and FSH) were measured by radioimmunoassay before and after intravenous injection of 0.1 mg/m2 of synthetic luteinizing hormone-releasing hormone in 20 male patients, aged 15 to 18 years, with constitutional delay of puberty. Basal plasma levels of LH and FSH were in the prepubertal range. After administration of LH-RH, the increase in LH was significantly high than in prepubertal control subjects, aged 1 to 13 years; the difference between test patients and pubertal control subjects was not significant. The increase in FSH was in the prepubertal range, significantly lower than that in pubertal control subjects. This discrepancy between LH and FSH responses to LH-RH is similar to that observed in normal boys at the late prepubertal stage and suggests that an elevation of readily releasable pituitary stores of LH correlates with the first step of pubertal onset in males, even if puberty is delayed.     

Precocious puberty: clinical and endocrine profile and factors indicating neurogenic precocity in Indian children

The objective of this study was to evaluate the clinical and endocrine profile of patients with precocious puberty followed up in a tertiary care hospital. Records of 140 patients (114 girls, 26 boys) with precocious puberty were reviewed. Clinical features including age of onset, stage of pubertal development, presenting symptoms, features suggestive of CNS involvement and family history were analyzed. Endocrine investigations included basal and GnRH-stimulated levels of LH and FSH as well as 17OHP, DHEA, hCG and thyroid profile. Abdominal and pelvic ultrasonography and CNS imaging were correlated with clinical features. Girls outnumbered boys in this series (4.4:1). Neurogenic central isosexual precocious puberty (CIPP) was more common in boys (10 out of 18, 55.6%) than girls (16 out of 77, 20.8%). The most common cause of neurogenic CIPP was hypothalamic hamartoma present in five girls and four boys. Other causes of neurogenic CIPP included neurotuberculosis, pituitary adenoma, hydrocephalus, post radiotherapy, CNS tumors and malformations. Peripheral precocious puberty (PPP) was secondary to adrenal causes in boys and ovarian cysts in girls. Benign variants of precocious puberty, such as premature thelarche and premature adrenarche, were present in 23 and six girls, respectively. Hypothyroidism was present in four girls and McCune-Albright syndrome in one girl. Girls with neurogenic CIPP had a lower age of onset as compared to idiopathic CIPP (3.6 +/- 2.7 years vs 5.4 +/- 2.5 years, p = 0.014). The lowest age of onset was seen in girls with hypothalamic hamartoma (1.6 +/- 0.9 years). Forty-seven girls with CIPP (seven neurogenic and 40 idiopathic) presented after the age of 6 years. Features of CNS involvement, in the form of seizures, mental retardation, raised intracranial tension or focal neurological deficits, were present in seven girls (43.8%) and four boys (40%), and gelastic seizures were present in three children. Girls with CIPP had greater bone age advancement (3.4 +/- 1.5 years) and negative height standard deviation for bone age (-2.7 +/- 1.5) than those with PPP (1.9 +/- 1.6 years and -1.3 +/- 1.3) and premature thelarche (0.4 +/- 0.4 years and -0.8 +/- 0.8). Patients with neurogenic CIPP had significantly higher levels of baseline and GnRH-stimulated levels of LH and FSH and LH:FSH ratio than those with idiopathic CIPP. Occurrence of neurogenic CIPP in seven girls with an age of onset after 6 years emphasizes the need for CNS imaging in these girls contrary to the current recommendations. The fact that 65.6% cases of idiopathic CIPP presented after the age of 6 years raises the possibility that these patients may be physiological variants of normal puberty. Pointers to neurogenic CIPP included early age of onset in girls, clinical features of CNS involvement, and elevated basal and stimulated LH levels and LH:FSH ratio.     

小于胎龄儿青春前期女孩硫化脱氢表雄酮和胰岛素水平的研究

目的探讨小于胎龄儿(SGA)青春前期女孩肾上腺机能初现及是否具有肾上腺机能早现、高肾上腺雄激素血症、高胰岛素血症和胰岛素抵抗现象。方法以符合纳入标准的SGA 39例为研究对象,年龄(7.4±1.7)岁,42例适于胎龄儿(AGA)为对照组,年龄(7.4±1.7)岁。在隔夜空腹12 h后,行身体检查,并抽血检测空腹血糖、胰岛素、硫化脱氢表雄酮(DHEAS)、皮质醇和雌二醇。胰岛素敏感性用空腹血糖与胰岛素乘积的倒数再取自然对数来评价。结果两组中未发现肾上腺机能早现的临床表现,两组间孕母孕龄、年龄、体重指数、空腹血糖、皮质醇、雌二醇和胰岛素敏感性指数差异无统计学意义。SGA组出生体重、研究时的身高和体重均低于AGA组,SGA血清胰岛素和DHEAS水平均高于AGA组(对数转换值:1.076±0.041vs.1.050±0.051,P<0.05;2.637±0.271vs.2.514±0.250,P<0.05)。AGA组DHEAS值在7岁以后出现明显增加,SGA组DHEAS值出现增加的趋势与AGA组比较有所提前。结论AGA女孩肾上腺机能初现的年龄约为7岁,而SGA女孩肾上腺机能初现有始动提前的趋势,青春前期SGA女孩有高肾上腺雄激素血症和胰岛素水平升高的现象,但以胰岛素敏感性指数来评价,尚未发现胰岛素抵抗现象。     

Premature thelarche in Taiwanese girls

This study was conducted to understand the clinical features and natural course of Taiwanese girls with premature thelarche (PT). The medical records of 91 Taiwanese girls with PT who were diagnosed younger than six and have been regularly followed up for more than two years were reviewed. For comparison, GnRH test was also done in 25 girls with central precocious puberty (CPP) and 10 normal prepubertal girls. The age of onset of these patients was 1.5 +/- 1.6 years and 79% of them developed PT before the age of two. Girls with PT had intermediate degree of hypothalamic-pituitary-ovarian activity between prepuberty and CPP with FSH-predominant response to GnRH stimulation. 87% of patients have complete regression of breast development during 3.8 +/- 2.5 years' follow-up but 19% of them have progressed to CPP during follow-up. We conclude that Taiwanese girls with PT more often developed within the first two years of life. Activation of hypothalamic-pituitary-gonadal axis with predominant FSH activity during infancy may contribute to its development. In addition, PT is not always a benign self-limited condition, and clinicians should be cautious about pubertal development of these patients.     

Onset of breast and pubic hair development in 1231 preadolescent Lithuanian schoolgirls.

BACKGROUND: Correct staging of puberty is essential in order to differentiate different pathologies, as various components of the endocrine system influence breast, pubic, and axillary hair development. AIMS: To determine the current timing of adrenarche and breast development in Lithuanian preadolescent schoolgirls. METHODS: Cross-sectional study of 1231 schoolgirls aged 7.0-11.6 years. Puberty was staged according to the method of Tanner. Mean age at entry into each pubertal stage was calculated by probit analysis. RESULTS: Of the 255 girls aged 7 years, two had premature adrenarche (0.8%) and one premature thelarche (0.4%). Mean age of onset of pubic/axillary hair development was 11.0 years, and for breast development (Stage 2) 10.2 years. Breast Stage 3 development was attained at 11.3 years and Stage 4 at 13.9 years. Mean BMI, height, weight, and systolic blood pressure SD scores were higher in pubertal than in prepubertal girls. Skinfold thickness was also significantly higher in girls with isolated adrenarche than in prepubertal girls. The increase in BMI and weight resulted from an increase in body fat as evidenced by measures of subscapular and triceps skinfold thickness. Girls with only signs of adrenarche or thelarche did not differ from each other from the anthropometric standpoint. CONCLUSIONS: Premature thelarche and premature adrenarche were relatively uncommon in this population. Pubertal onset was slightly earlier than the UK Tanner standards and tended to occur in girls with a higher BMI.     

Isolated breast prematurity in young girls

The clinical and follow-up data of the isolated premature thelarche are reviewed in a series of 61 girls aged 6 months to 6 years. Transitory increase of plasma estrogens was observed in some cases. The results of LHRH test were similar to those from normal girls of the same age. Premature thelarche could be a normal variant in girls, related with the physiologic unsteadiness of the prepubertal female pituitary-gonadal axis.     

Premature thelarche from phenotype to genotype

Premature thelarche is a benign condition, which has been described as a "variant of puberty". Early breast development is especially prevalent during the first year of life, when the gonadal axis is usually active. Ultrasensitive bioassays have described higher estrogen levels in these girls compared to controls. Some cases of premature thelarche may also exhibit increased growth velocity and/or bone age, despite prepubertal gonadotropin secretion. These cases have been labeled as exaggerated thelarche and may represent an intermediate state between benign premature thelarche and precocious puberty. Several factors have been associated with the etiology of premature thelarche, such as endocrine disruptors, and genetic and nutritional factors. Recently, it has been shown that some girls with exaggerated or fluctuating thelarche may have an activating mutation in the GNAS gene, which codifies for alpha subunit of G stimulating protein (Gsalpha). We discuss the different phenotypes that may be associated with PT and its etiology.     

Studies of gonadotrophin pulsatility and pelvic ultrasound examinations distinguish between isolated premature thelarche and central precocious puberty

We have studied the pulsatile secretion of gonadotrophins at night and made ovarian ultrasound examinations in three girls with central precocious puberty and three with isolated premature thelarche. The three girls with precocious puberty had well-defined pulsatile secretion of LH and FSH with LH predominating, as would be expected in normal puberty. Pulsatile secretion of gonadotrophins was also seen in girls with premature thelarche but the pattern was reversed. In girls with precocious puberty, large multicystic ovaries and large uteri were seen on ultrasound examination, whereas girls with isolated premature thelarche had small uteri and ovaries with less than four cysts up to 15 mm in diameter. These data provide the key to understanding the aetiology of isolated premature thelarche.Abbreviations GnRH gonadotrophin releasing hormone - LH luteinising hormone - FSH Follicle stimulating hormone - SDS standard deviation score     

LH-RH and HCG studies in a Turner phenotype male (Noonan's syndrome). A case report.

LH-RH and HCG stimulation tests were performed in a prepubertal 13-year-old boy with Noonan's syndrome. The basal plasma LH (0.8 mIU/ml) was normal and FSH (2.5 mIU/ml) high, with an elevated response of both LH (8.3 mIU/ml) and FSH (9.6 mIU/ml) to LH-RH, as seen in primary hypogonadism. However, the patient had a normal testosterone response to HCG (437 ng%). These conflicting test results illustrate the difficulty of predicting potential for fertility in patients with Turner phenotype male.     

Pulsatile secretion of luteinizing hormone and sleep-related gonadotropin rhythms in girls with premature thelarche

The concentrations of LH, FSH and PRL were determined in serum samples obtained at night in 1–2 h intervals as well as at 15 min intervals during a 3 h period between 9 and 12 p.m. and 9 and 12 a.m. in three girls with premature thelarche, who had not developed further signs of precocious puberty for more than 18 months.A sleep-dependent LH and FSH increase was documented in all of them with a predominance of FSH secretion during sleep and after LHRH stimulation. In all three girls an episodic pattern of LH was found during sleep. In daytime minor fluctuations of LH secretion were found in two patients whereas in one patient an episodic LH pattern was demonstrable with minor peak values as during sleep.Normal PRL secretion during sleep as well as after TRH stimulation excludes a permissive role of this hormone in premature thelarche.We conclude that in girls with isolated premature thelarche a matured hypothalamo-pituitary gonadotropin axis is active comparable to normal pubertal children.     

Pelvic ultrasonography: Early differentiation between isolated premature thelarche and central precocious puberty

We examined 55 girls with isolated premature thelarche between the ages of 0.3 and 7.3 years (group A), 20 children with central precocious puberty between 2.1 and 7.7 years of age and 101 age-matched controls. The children with precocious puberty were divided according to distribution of pubic hair into group B (Tanner stages PH1, B2–3;n=11), representing an early stage of the disorder, and group C (stages PH2–3, B3–4;n=9), representing an advanced stage. Uterine and ovarian volumes were measured sonographically, peak serum levels of luteinizing hormone and folliclestimulating hormone were determined after intravenous administration of luteinizing hormone-releasing hormone. The mean uterine and ovarian volumes were significantly greater in children with precocious puberty than in controls (group B: uterine volume: 3.8±2.0 ml vs 0.9±0.3 ml for controls,P<0.001; ovarian volume: 2.2±1.3 ml vs 0.6±0.2 ml for controls,P<0.01; group C: uterine volume: 8.0±4.4 ml vs 1.0±0.3 ml for controls,P<0.01; ovarian volume: 2.6±1.3 ml vs 0.4±0.1 ml,P<0.01). No significant differences were found between children with premature thelarche and the control group. As a diagnostic method for the early detection of central precocious puberty, ultrasound measurement of uterine volume had a sensitivity and specificity of 100% (cut-off value, 1.8 ml), while ultrasound determination of ovarian volume had a sensitivity of 82% and a specificity of 95% (cut-off value, 1.2 ml). In contrast, as a diagnostic criterion the ratio of levels of luteinizing hormone to follicle-stimulating hormone as determined following stimulation with luteinizing hormone releasing hormone had a sensitivity of 33% and a specificity of 100% (cut-off value, 1.0). Conclusion: ultrasonographic measurement of uterine and ovarian volume offers a reliable means of distinguishing between isolated premature thelarche and early stages of central precocious puberty.     

Effects of beta-2 agonist on hepatic glycogen metabolism in the fetal lamb

To determine the effects of fetal beta-2 agonist exposure on fetal hepatic glycogen metabolism, we infused ritodrine at a rate of 1.3 +/- 0.4 microgram/kg/min (mean +/- SD) for 24 h into six chronically catheterized twin fetal lambs starting between 128 and 134 days gestation. The control twins received 0.9% saline at 1.2 +/- 0.12 ml/kg/h. In addition, 15 uncatheterized fetuses were killed between 115 and 148 days gestation as unoperated controls. Ritodrine infusion produced a 1.7-fold elevation in fetal serum glucose level, from 23 +/- 5 to 42 +/- 15 mg/dl, and a 2-fold elevation in serum insulin level, from 16 +/- 5 to 34 +/- 8 mg/ml, p less than 0.01. Hepatic glycogen content increased 7-fold in the uncatheterized controls between 115 and 148 days gestation (r = 0.9, p less than 0.001). Ritodrine infusion reduced hepatic glycogen content by 50% from 179 +/- 19 micrograms/mg in twin controls to 90 +/- 25 micrograms/mg in the ritodrine-infused twins, p less than 0.001. Hepatic glycogen phosphorylase kinase activity was elevated 1.3-fold from 0.149 +/- 0.100 mU/mg protein in control twins to 0.186 +/- 0.007 mU/mg protein in the ritodrine infused twins, p less than 0.001. Glycogen phosphorylase a activity was also increased 1.4-fold from 8.60 +/- 0.76 nM NADPH/min/mg protein in control twins to 11.85 +/- 0.68 nM NADPH/min/mg protein in the ritodrine infused twins, p less than 0.001.(ABSTRACT TRUNCATED AT 250 WORDS)     

Premature Thelarche in Later Childhood Demonstrates a Pubertal Response to GnRH Stimulation Test at One Year after Breast Development

Premature thelarche in later childhood (such as at 5–7 yr of age) is not always easy to distinguish from GnRH-dependent precocious puberty. In this study, a GnRH stimulation test was performed on 21 girls from 5 to 7.5 yr of age with early breast development. In 8 of 11 girls within 1 yr after thelarche, i.e., breast development, the GnRH stimulation test showed a prepubertal response, and in all 10 girls at more than 1 yr after breast development, the GnRH stimulation test showed a pubertal response. In observations of 4 girls with a prepubertal response, the GnRH stimulation test showed to a pubertal response by 1 yr or more after breast development in 3 of 4 the girls. These results indicate the possibility that almost all cases of breast development in later childhood consist of premature thelarche and that premature thelarche in later childhood may easily lead to early puberty at 1 yr or more after breast development. Careful observations are therefore recommended for at least 1 yr, even if early breast development is considered to be associated with premature thelarche in later childhood.