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1.
The relation between women's timing of menarche and father absence was examined in a national probability sample of Great Britain (NATSAL 2000; N>5000). Current body mass index (as a proxy for childhood weight) was examined as a potential mediator of this relationship, along with the potential moderating role that siblings (e.g. number of older brothers) had on this relationship. As in a number of previous studies, an absent father (but not an absent mother) during childhood predicted an earlier age of puberty (i.e. an early menarche). There was no evidence that weight mediated this relationship or that siblings moderated it. Both a lower body mass index and more siblings (e.g. more younger sisters and brothers) were independent predictors of a later timing of puberty. The results confirm that certain psychosocial factors (i.e. father absence; presence of siblings) may affect the timing of sexual maturation in adolescent girls.  相似文献   

2.
Growth, age at menarche and spontaneous GH secretion were studied in girls after treatment for acute lymphoblastic leukemia (ALL). These girls had normal prepubertal growth but subnormal pubertal growth. Mean final height was 1 SD less than expected before puberty. The average age at menarche was significantly lower than the normal mean for Swedish girls. The mean 24-hour GH secretion was severely blunted and there was no increase during puberty. We suggest that girls treated for ALL, including CNS irradiation, have a relative GH insufficiency which becomes clinically obvious only when the girls cannot respond to the increased demands for GH in puberty.  相似文献   

3.
An initial group of 200 girls, 7-17 years old, was investigated longitudinally 4 times at 1.5-, 1.5- and 5-year intervals. The present study gives information of the impact of early menarche, a risk factor for breast cancer, on some physical and endocrine characteristics in these subjects. The frequency of ovulation depended significantly on both the time since menarche and the age at menarche. Early menarche was associated with early onset of ovulatory cycles. Even in early puberty, before menarche, the subjects who displayed early menarche during follow-up had higher serum FSH and estradiol concentrations than the girls whose menarche took place after the age of 13.0 years. Adrenal androgen secretion (dehydroepiandrosterone) was not influenced by age at menarche but it increased, as expected, on the basis of chronological age. The group with early menarche was characterized by high circulating estradiol concentrations also after menarche, even in the oldest subjects so far studied, 17-25 years of chronological age. At these ages, the differences in the frequencies of ovulatory cycles were disappearing between the groups formed on the basis of age at menarche. The present findings in pre- and postmenarcheal subjects suggest that the increased risk of breast cancer associated with early menarche is created over several years of exposure to high-level estrogen stimulus.  相似文献   

4.
OBJECTIVES: To determine the timing, magnitude and duration of the pubertal spurt for short normal and average height girls, to compare these with Tanner's standard and to investigate predictors of pubertal growth. METHODS: The growth of 46 short normal and 55 control girls, identified at school entry, was monitored throughout puberty. Height and weight were measured at 6-month intervals from which body mass index (BMI) was derived. Annual velocities were calculated and used to estimate the age and magnitude of peak height velocity (PHV). Age of menarche was recorded to the nearest month. Parents provided information on the child's medical and social history. RESULTS: The mean age at PHV, the magnitude of PHV and age at menarche were similar for both groups and close to Tanner's 50th centile values. Pre-pubertal BMI predicted age at menarche for short and control girls, accounting for 17% of the variance. There was a tendency for early maturing girls of average stature to have greater PHV. However, this relationship was not observed in short girls, nor did any other variable, genetic or environmental, predict the timing or magnitude of their pubertal spurt. CONCLUSIONS: Delayed puberty in short normal girls is unlikely and their growth during puberty is comparable to girls of average height. The pubertal variables measured remain close to Tanner's original standards for both groups, suggesting the lack of a secular trend towards earlier puberty in girls. The onset of menstruation is influenced by pre-pubertal BMI. However, the clinician should be aware that short normal girls have normal pubertal growth and that no genetic or environmental variable can predict the timing or magnitude of their growth spurt.  相似文献   

5.
Assessments of skeletal age are a valuable adjunct to the clinical evaluation of physical maturity but are more meaningful when considered in relation to chronological age, especially over time, than as separate entities. Data on 51 girls from the Child Research Council study series gave a correlation coefficient of 0.51 between skeletal age (SA) at menarche and chronological age (CA) at menarche — a value in close agreement with data reported from other studies. With a range in SA of 11.58 to 14.89 years, these data were examined further for changes in SA related to timing of adolescence. SA was greater than CA in each of the nine girls whose menarche occurred between 10.5 and 12 years of age. SA was equal to CA in one girl, greater than CA in eight girls and less than CA in 11 girls with menarche between 12.15 and 13.4 years. Of the 22 girls with menarche after 13.5 years, one had SA = CA at 14.89 years and the other 21 all had SA less than CA. An r of 0.84 was calculated between the values of CA minus SA at menarche and CA at menarche. Similar relationships were found between SA and CA at age of maximum increment in growth in height for these girls and for 53 boys in the study series. Longitudinal data for height, weight and SA for four boys and five girls demonstrate the problems of prediction of the timing of adolescence and of adult size from skeletal ages in the childhood years.  相似文献   

6.
In females, menarche is the defining moment of puberty, the period of life when the greatest body changes occur. In the present study, the metric and morphological variations associated with sexual maturation are defined in 155 Sardinian girls (10-17 years) and the role of some potentially influential variables is discussed: age, age at menarche and time since menarche. We studied thirty-eight anthropometric variables, the fat-free mass and the fat mass estimated by Bioelectrical Impedance Analysis. Statistical analyses were performed to evaluate the difference between pre- and post-menarcheal girls of the same age (Student's t-test) and to evaluate the different role played by the variables (principal components analysis, cluster analysis, multiple regression). The results demonstrate that the body dimensions of the adolescent girls mainly increase in concomitance with sexual maturation. The age at menarche influences the fat mass but not the distribution of visceral and subcutaneous fat. The time since menarche has also no effect on the distribution of subcutaneous fat.  相似文献   

7.

Objective

To examine the influence of childhood obesity on the early onset of puberty and sex hormones in girls.

Methods

Healthy girls with different percentages of body fat at baseline (40 obese, 40 normal, and 40 lean) were recruited from three elementary schools in Shenyang, China. These girls (mean age 8.5 years) were also matched by height, school grade, Tanner stage, and family economic status at baseline. Anthropometry, puberty characteristics, and sex hormone concentrations were measured at baseline and at each follow-up visit. The generalized estimating equation model and analysis of variance for repeated measures using a generalized linear model were used to determine the differences in puberty characteristics and sex hormones among three groups.

Results

Over 4 years, mean age of breast II onset was earlier among obese girls (8.8 years) than normal girls (9.2 years) and lean girls (9.3 years). The prevalence (%) of early-maturation in the obese, normal, and lean groups was 25.9%, 11.1%, and 7.4%, respectively. Obesity was associated with an increased risk for breast stage II (year 2: RR, 6.3; 95% CI, 1.9–21.1 and year 3: RR, 6.9; 95% CI, 0.8–60.1). None of the girls experienced menarche in the first year; however, by the fourth year 50.0% of obese girls had menarche onset, which was higher than normal weight (27.5%) and lean girls (8.1%). The mean estradiol level increased with age in the obese, normal, and lean groups. The mean estradiol concentration was higher in obese girls than in normal and lean girls throughout the 4-year period (P<0.05).

Conclusions

Childhood obesity contributes to early onset of puberty and elevated levels of estradiol in girls.  相似文献   

8.
The age at menarche and menopause of three groups of Bhotia females living at high altitude, Himalayan region — Uttar Pradesh, North India, were studied. The Johari Bhotia women had earliest menarche (¯X=15.1±1.1 years) as compared to Rang Bhotias, settled (¯X=15.6±0.9 years) and Rang Bhotias, migratory (¯X=16.0±1.0 years). The differences between all these three groups for age at menarche were significant. A trend towards increase in age at menarche with an increase in altitude has been observed, but the total fertility period in the three groups remained similar as early menarche has been found to be associated with early onset of menopause and late menarche with late menopause.  相似文献   

9.
The auxological data of 25 patients (21 girls, 4 boys) with central precocious puberty (CPP), treated for 4 years with a slow-release gonadotropin-releasing hormone agonist [Decapeptyl-controlled release (D-CR) 3.75] every 4 weeks intramuscularly, and of 6 patients (3 girls, 3 boys), treated for 5 years, are presented. After 3 years of D-CR a stabilization of height velocity (HV) at about 4 cm/year was observed. Bone maturation (ratio of change in bone age to change in chronological age; delta BA/delta CA) slowed down to a mean delta BA/delta CA ratio of 0.5 +/- 0.2 (mean +/- SD) measured over 48 months. As a result, predicted adult height (PAH) improved from 156.3 +/- 7.4 to 162.2 +/- 6.8 cm in girls (p less than 0.001) and from 174.4 +/- 18.6 to 184.3 +/- 17.1 cm in boys after 4 years. In the 5th year an ongoing improvement of PAH was observed. 20 additional girls discontinued D-CR for at least 12 months after treatment with D-CR for 2 years or more. In 11 girls menses started after 10.6 +/- 3.1 months; 9 girls had no menarche after 12-16 months. HV increased in the first and second 6 months to a level of about 6.0 cm/year, decreased in the third 6 months after cessation to the level before discontinuing D-CR and decreased further afterwards. Bone maturation (delta BA/delta CA) increased progressively in the first 18 months after discontinuation, with a stabilization at about 1.3. PAH did not change in the first 12 months after discontinuation of D-CR, but showed a decrease afterwards.(ABSTRACT TRUNCATED AT 250 WORDS)  相似文献   

10.
Puberty is a critical period in body composition development. The influence of puberty on the development of fat mass asks for further investigation. We investigated the development of fat mass during puberty in a longitudinal prospective study in 152 healthy nonobese white girls, initial ages between 9 to 12 years. The influence of menarcheal age and the existing of tracking of fat mass have been analyzed. In 10 years time, participants were measured on eight time points. Various anthropometric data were collected, breast development was staged according to Tanner and body composition was determined with the dual‐energy X‐ray absorptiometry (DXA) scan. Calculations were made with the use of a linear mixed model. Fat mass increases from 7.9 kg (23.6%) at B1 to 18.5 kg (29.3%) at B5. Fat mass is higher in girls with an early menarche than in girls with a late menarche from B2. Girls in the quartile with initially the lowest fat mass have a chance of being in the same quartile after 10 years of 77% (P < 0.001). Girls in the quartile with initially the highest fat mass, have a risk of staying in the highest quartile of 55% (P < 0.001). Menarcheal age is of great influence on the development of fat mass. Girls with an early menarche, will have a bigger fat mass, especially at the end of puberty. Tracking of fat mass exists: a high amount of fat mass in early puberty will continue to exist at young adulthood.  相似文献   

11.
Several studies have shown that there is a Northwest-Southeast gradient in menarcheal age of European girls, with menarche occurring on the average about one year earlier in girls living in the Southern parts of Europe as compared with those from the Northern and Northwestern European countries. Eveleth & Tanner (1976) as well as Danker-Hopfe (1986a) suggested that this gradient is due primarily to genetic differences rather than climatic or nutritional variation. To substantiate this hypothesis menarcheal age of Turkish girls who lived in Bremen for several years has been investigated. The mean age at menarche estimated by probit analysis based on status quo data from n = 494 girls aged from 9.0 to 16.5 years was 12.90 +/- 1.21 years. These results correspond very well to those reported by Neyzi et al. (1975) for girls from Istanbul. On the other hand mean menarcheal age of Turkish girls living in Bremen is distinctly lower than mean age at menarche of urban German girls, living in the same district. In summary the results of the present study support the hypothesis of a predominantly genetic cause for the observed Northwest-Southeast gradient in age at menarche in Europe.  相似文献   

12.

Aim

To assess and compare the secular trend in age at menarche in Dutch girls (1955–2009) and girls from Turkish and Moroccan descent living in the Netherlands (1997–2009).

Methods

Data on growth and maturation were collected in 20,867 children of Dutch, Turkish and Moroccan descent in 2009 by trained health care professionals. Girls, 9 years and older, of Dutch (n = 2138), Turkish (n = 282), and Moroccan (n = 295) descent were asked whether they had experienced their first period. We compared median menarcheal age in 2009 with data from the previous Dutch Nationwide Growth Studies in 1955, 1965, 1980 and 1997. Age specific body mass index (BMI) z-scores were calculated to assess differences in BMI between pre- and postmenarcheal girls in different age groups.

Results

Median age at menarche in Dutch girls, decreased significantly from 13.66 years in 1955 to 13.15 years in 1997 and 13.05 years in 2009. Compared to Dutch girls there is a larger decrease in median age of menarche in girls of Turkish and Moroccan descent between 1997 and 2009. In Turkish girls age at menarche decreased from 12.80 to 12.50 years and in Moroccan girls from 12.90 to 12.60 years. Thirty-three percent of Turkish girls younger than 12 years start menstruating in primary school. BMI-SDS is significantly higher in postmenarcheal girls than in premenarcheal girls irrespective of age.

Conclusion

There is a continuing secular trend in earlier age at menarche in Dutch girls. An even faster decrease in age at menarche is observed in girls of Turkish and Moroccan descent in the Netherlands.  相似文献   

13.
Stature and body weight data of 100 boys and 100 girls from 7 to 17 years of age in Shimodate City who were born during World War II were longitudinally analyzed. The children were significantly smaller and lighter throughout their growth period than those born 11 years after the end of the war. The correlation coefficient between statures at each age and at age 17 showed a gradual increase with increasing age, while that between statures at each age and at age 7 decreased with age. However, a drop in the correlation coefficient was found during puberty, at age 11 for girls and at age 13 for boys. Comparing the normalized distance from mean values of stature and body weight at age 7, at puberty, and at age 17, only 51% of the children continued to be in the same relative position for both height and weight, 6% of boys and 4% of girls showing a decreasing pattern for both and 4% of boys and 7% of girls showing an increasing pattern for both. Thus, about 60% of the children of either sex presented parallel stature and body weight growth patterns for ages from 7 to 17.  相似文献   

14.
Age at menarche is regarded as a sensitive indicator of physical, biological, and psychosocial environment. The aim of this study was to determine the age at menarche and its association with biological and socioeconomic factors in girls from Santa Rosa (La Pampa, Argentina). An observational cross-sectional study was carried out on 1,221 schoolgirls aged 9-15 years. Menarche data were obtained by the status-quo method. Height, sitting height, weight, arm circumference, tricipital and subscapular skinfolds were measured. We also calculated body mass index, measures of body composition and proportions, and fat distribution. To assess socioeconomic factors, parents completed a self-administered questionnaire about their occupation and education, family size, household, and other family characteristics. The median age at menarche - estimated by the logit method--was 12.84 years (95% CI: 12.71, 12.97). Compared with their premenarcheal age peers, postmenarcheal girls had greater anthropometric dimensions through age 12. After this age, only height was higher in the latter group. Data were processed by fitting two logistic regressions, both including age. The first model included anthropometric variables and birth weight, while the second model included the socioeconomic variables. The significant variables derived from each model were incorporated into a new regression: height, sitting height ratio (first model), and maternal education (second model). These three variables remained significantly associated with menarche. The results suggest a relationship between linear growth and menarche and agree with those found in other populations where the advancement of menarche is associated with improved living conditions. In relatively uniform urban contexts, maternal education may be a good proxy for the standard of living.  相似文献   

15.
There is increasing evidence for a link between prenatal growth and pubertal development. Here we highlight a selection of pubertal characteristics in children who were born small for gestational age (SGA). Boys born SGA are at risk of high levels of follicle-stimulating hormone (FSH) and low levels of inhibin B and a small testicular volume during adolescence. In girls born SGA, the age at pubertal onset and the age at menarche are advanced by about 5-10 months; prenatal growth restraint may also be associated with higher FSH levels and smaller internal genitalia in adolescence. The ovulation rate was found to be reduced in adolescent girls born SGA, and an insulin-sensitizing therapy was capable of raising this low ovulation rate. Menarche is definitely advanced in girls born SGA with precocious pubarche and in those with an early-normal onset of puberty. Current evidence suggests that insulin resistance is a key mechanism linking a post-SGA state to early menarche; hence, insulin sensitization may become a valid approach to prevent early menarche and early growth arrest in girls born SGA.  相似文献   

16.

Purpose

Studies indicate that milk intake is associated with insulin-like growth factor 1 (IGF-1) concentrations and height in childhood, whether milk and other dairy products promote puberty remains unclear. This study aimed to investigate influences of pre-pubertal intakes of milk, yogurt and cheese on menarcheal age in Tehranian girls. The associations of total dietary calcium (Ca), magnesium (Mg), and phosphorus (P) with menarcheal age were also examined.

Methods

This prospective study was conducted on 134 pre-pubertal girls, aged 4-12 years at baseline, who participated in the Tehran Lipid and Glucose Study (TLGS), and were followed for a median of 6.5 years. Dietary intakes were determined at initiation of the study using two non-consecutive 24-h dietary recalls and the age of menarche was documented during the follow-up. Logistic regression was used to calculate the risk of reaching menarche ≤ 12 years according to pre-pubertal levels of dairy or mineral intakes.

Results

The risk of earlier menarche was higher in girls with higher intakes of milk [OR: 2.28 (95% CI: 1.03–5.05)], Ca [OR: 3.20 (95%CI: 1.39–7.42)], Mg [OR: 2.43 (95% CI: 1.12–5.27)] and P [OR: 3.37 (95 % CI: 1.44–7.87) after controlling for energy and protein intake, interval between the age at study initiation and the age of menarche, and maternal age at menarche (Model 1). Girls in the middle tertile of cheese intakes had a lower risk of reaching menarche ≤ 12 years than those in the lowest tertile after controlling for covariates in model 1. These associations remained significant after further adjustment of BMI Z-score at baseline. The relationship of Ca, Mg, and P with menarche remained after further adjustment for height Z-score at baseline, whereas the association between milk and cheese intakes became non-significant.

Conclusions

Pre-pubertal intake of milk, but not cheese and yogurt, may hasten age at menarche.  相似文献   

17.
Gonadotropin pulsatile secretion in girls with premature menarche   总被引:1,自引:0,他引:1  
Five prepubertal girls (2.3-8.1 years old) were studied for isolated or recurrent vaginal bleeding in the absence of other signs of precocious puberty (premature menarche). Four of these girls with recurrent vaginal bleeding were studied for pulsatile gonadotropin secretory patterns. During sleep 3 girls showed luteinizing hormone (LH) pulses with low amplitude and a pubertal pattern of frequency whereas follicle-stimulating hormone (FSH) increased without demonstrable episodic secretion. Luteinizing hormone-releasing hormone (LHRH) tests demonstrated that FSH responses are greater than the LH responses, as in prepuberty. In 3 cases estradiol levels had augmented above normal prepubertal range. The menses spontaneously stopped during the follow-up. A reevaluation of the gonadotropin pattern, having the menses stopped for 6 months, in one of the girls with pulsatile LH secretion showed an apulsatile prepubertal LH pattern. Also estradiol levels returned to prepubertal range. A follow-up of 10-66 months of these patients did not show any growth and bone acceleration or signs of precocious puberty. Our data suggest that in premature menarche a partial and transient activation of hypothalamo-pituitary axis could be present. Premature menarche seems to be a benign and self-limiting condition and one of the girls had a normal onset of puberty during follow-up.  相似文献   

18.
AIM: To describe the effects of chronological age and biological age (pubertal development) on serum lipid and lipoprotein levels, body mass index (BMI) and waist circumference in Spanish adolescents. METHODS: A representative Spanish sample of 526 adolescents (254 males and 272 females), were studied. Total cholesterol (TC), high density lipoprotein cholesterol (HDLc), triglycerides, apolipoprotein A1 and B, and lipoprotein(a) were measured, and low density lipoprotein cholesterol (LDLc) was calculated. Additional measurements included BMI and waist circumference. Adolescents were classified according to chronological age, and pubertal development (also age of menarche in females). RESULTS: In males, serum TC levels were lower at late puberty in comparison with early puberty, and serum LDLc levels were lower at late puberty in comparison with mid and early puberty. Serum HDLc levels were lower at mid puberty in comparison with early and late puberty. Serum TC and LDLc levels were not different when analyzed according to chronological age. In females, HDLc levels were lower at late puberty in comparison with early and mid puberty, but no differences were found when HDLc and the other studied lipid and lipoprotein variables were analyzed according to chronological age, or age of menarche. All the observed differences persisted after adjusting for BMI and waist circumference. In female adolescents, both BMI and waist circumference were higher at late puberty in comparison with early and mid puberty, while in males, BMI and waist circumference were different when analyzed according to chronological age. CONCLUSION: The results suggest that the assessment of pubertal development may provide additional valuable information when interpreting lipid profile and body fat in adolescents.  相似文献   

19.
We have studied 41 children with early or precocious puberty who have been treated for acute lymphoblastic leukaemia with prophylactic cranial irradiation (1,800-2,400 cGy) accompanied by intrathecal methotrexate and systemic chemotherapy. Mean age at radiotherapy was 3.9 years (range 1.7-7.7) in the girls and 4.8 years (range 2.6-7.8) in the boys. Mean age at the onset of puberty was 8.6 years (range 6.7-9.7) in the girls and 9.3 years (range 7.8-10.3) in the boys. Of the 41 children with early puberty (greater than 1.4 SD from the mean) 36 were females and 5 were males. 21 of the 36 girls had an absent or inadequate growth acceleration of puberty. 7 of 12 girls who had a pharmacological test of growth hormone (GH) secretion had GH insufficiency (peak level less than 20 mU/l). Early or precocious puberty combined with GH insufficiency may produce severe growth failure and we have used a treatment regimen of a gonadotrophin-releasing hormone analogue, in order to reduce the rate of epiphyseal maturation, combined with biosynthetic GH to increase or sustain growth rate. We have treated 4 girls in this manner. During a mean treatment period of 0.86 years, height SDS for bone age rose from a mean of -1.06 to -0.59. Longer treatment periods will be required to assess the effect on final height.  相似文献   

20.
Recently, few studies regarding the changes in BMI with age have been reported. In the present study, the wavelet interpolation method (WIM) was applied to the changes in BMI with age from the first grade of elementary school until the second year of high school in Korean girls, and the relationship between age at the maximum peak velocity (MPV) of BMI and age at menarche was confirmed by determining the age at MPV of BMI. Age at menarche and activity status were obtained from questionnaires given to 263 second grade high school girls in the Pusan area of South Korea. Moreover, longitudinal growth data on height and weight from the first grade of elementary school until the second year of high school (from 1997 to 2008) were obtained from health examination records. BMI was calculated from height and weight values from the first grade of elementary school until the second year of high school, and wavelet interpolation was applied to the distances of BMI in each grade. The change curve of BMI with age was determined by wavelet interpolation, and the age at MPV of BMI was determined from the changes in the velocity curve with age as the differentiation curve. Age at MPV of BMI was found to be 12.76 +/- 1.6 years, and age at menarche to be 12.34 +/- 1.1 years. The interval in age at the two times was -0.42 +/- 1.6 years, and a significant difference was seen between age at menarche and age at MPV of BMI. The reason that the age at menarche was a little earlier than the age at MPV of BMI is hypothesized to be abnormal melatonin levels influenced by lack of sleep in Korean school girls. However, it is proposed that the age at MPV of BMI is valid as the critical period for the age at menarche.  相似文献   

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