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1.
Paternal investment theory and psychosocial acceleration theory hold that father absence and stressful experiences, respectively, accelerate reproductive development. Accumulating evidence is consistent with these theories yet important questions remain. In this study, we use a two-part structural equation model and data from 342 female undergraduates to address two of these questions: First, what is the role of father absence in female psychosocial acceleration, controlling potentially confounding aspects of environment and family structure? Second, to what extent does age at menarche mediate environmental and family structure effects on sexual debut? Findings indicated that many aspects of environment and family structure could be summarized with two factors—socio-economic status (SES) and fragmented family structure. We found that among those who had experienced sexual debut, exposure to temporary father departure (one year or more) in the context of an intact family hastened menarche, which in turn accelerated sexual debut. However, this type of father absence did not predict experience of sexual debut (or not). Fragmented family structure (which also implies some degree of father absence) appeared to increase the likelihood that participants had experienced sexual debut, but did not predict age at menarche or age at sexual debut among who had debuted. SES was not associated with any aspects of reproductive development, controlling for fragmented family structure and age. We discuss our findings in relation to paternal investment theory, psychosocial acceleration theory, and life history theory. We then lay out future directions for researchers aiming to clarify the role of environment in reproductive trajectories.  相似文献   

2.
Father absence is consistently associated with children’s reproductive outcomes in industrialized countries. It has been suggested that father absence acts as a cue to particular environmental conditions that influence life history strategies. Much less is known, however, about the effects of father absence on such outcomes in lower-income countries. Using data from the 1988 Malaysian Family Life Survey (n?=?567), we tested the effect of father absence on daughters’ age at menarche, first marriage, and first birth; parity progression rates; and desired completed family size in Malaysia, a country undergoing an economic and fertility transition. Father absence during later childhood (ages 8 to 15), although not during earlier childhood, was associated with earlier progressions to first marriage and first birth, after controlling for other confounders. Father absence does not affect age at menarche, desired family size, or progression from first to second birth. The patterns found in this transitional population partly mirror those in developed societies, where father absence accelerates reproductive events. There is, however, a notable contrast between the acceleration in menarche for father-absent girls consistently found in developed societies and the lack of any association in our findings. The mechanisms through which father absence affects reproduction may differ in different ecological contexts. In lower-income contexts, direct paternal investment or influence may be of more importance in determining reproductive behavior than whether fathers act as a cue to environmental conditions.  相似文献   

3.
The author reports on the results of investigations concerning the development of 15173 girls born in G?rlitz between 1944 and 1973. With regard to maturation a significant tendency toward deceleration has been observed. Late menarche is increasing, while early menarche is decreasing. Seasonal influences on the development are discussed. September born girls, for example, are characteristic for a high menarcheal age, those born in December for a low menarcheal age. Furthermore one can assume some relations between the month of birth and the birthweight.  相似文献   

4.
We examined secular changes in mean age at menarche among 5577 Colombian women born between 1941 and 1989, and correlated those changes with nation-wide rates of homicide and real gross domestic product per capita (GDP) at the year of birth and at the year at age 5, within predefined historical periods. The mean (standard error) rate of change in age at menarche by year of birth was −0.55 (0.02) years/decade. The rate of change was not constant, but varied between historical periods as follows: −1.44, −0.14, −0.60, and −0.36 years/decade for the periods 1941–1947, 1948–1958, 1959–1978, and 1979–1989, respectively. The changes in age at menarche correlated positively with the changes in the nation-wide rates of homicide within such periods; i.e. decelerations in the menarcheal trend coincided with increases in the rates of homicide and vice versa. The correlation was higher with the rates of homicide when women were 5 years of age (r = 0.99, p = 0.01) compared to the rates of homicide at the year of birth (0.55, p = 0.45). There were negative correlations between the changes in age at menarche and the changes in GDP, but they were weaker than those with the rates of homicide. These results could suggest a potential impact on maturation of psychosocial stress in childhood due to exposure to a generalized atmosphere of violence and fear.  相似文献   

5.
Menarche, menopause and reproduction in the Kipsigis of Kenya   总被引:1,自引:0,他引:1  
Among the Kipsigis, a population of south-western Kenya who do not use contraception, age at menarche and age at last live birth could be determined for a cohort of post-menopausal women, through reference to clitoridectomy ceremonies that can easily be dated. While a woman's age at last live birth was strongly associated with the length of her reproductive lifespan, completed family size was better predicted by age at menarche. The demographic implications of variation in menarcheal age are discussed.  相似文献   

6.
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   

7.
Given the ambiguity surrounding the source of the continuing trend toward earlier menarche observed in Westernized nations, several competing explanatory models have emerged regarding variation in pubertal timing. While a biomedical model proposes that predominantly constitutional characteristics shape the maturation timetable, an alternative framework derived from Life History Theory (LHT) evolutionary principles emphasizes the influence of psychosocial factors on development. Working with a sample of women 19?C25?years of age (N?=?103) drawn from two Southeastern U.S. colleges, we combined cultural consensus analysis with retrospective self-report regarding childhood stress and menarcheal timing to investigate whether reported developmental experiences align with cultural models regarding factors that should drive pubertal timing. Results suggest a robust cultural model consistent with a biomedical framework concentrating principally on constitutional characteristics. However, participants?? personal developmental recollections support an association between higher childhood stress and earlier menarche. These findings support LHT predictions that early reproductive maturation is an evolutionary adaptive response to chronic childhood stress as well as clarify the extent to which cultural models of factors contributing to puberty concord with developmental experiences.  相似文献   

8.
Objective: Children with birth weight appropriate for gestational age (AGA) who also demonstrate rapid weight gain in infancy have a greater risk of being overweight or obese during childhood. A concurrent advancement in skeletal maturity would account for their greater size and would, therefore, not necessarily pose a threat of greater risk during adolescence and early adulthood. This study aims to determine whether children with rapid weight gain during infancy have advanced skeletal maturity during childhood. Research Methods and Procedures: One hundred and ninety‐three African children (boys = 108; girls = 85) of normal birth weight and gestational age were assessed from birth to 9 years. Body composition was assessed at 9 years of age by whole‐body DXA, and skeletal maturity was assessed using the Tanner‐Whitehouse II technique. Rapid weight gain in infancy was defined as a +0.67 change in weight‐for‐age Z‐score between birth and 2 years. Results: Rapid weight gain was experienced by over 20% of the sample. Children with rapid weight gain were significantly lighter at birth and significantly taller, heavier, and fatter throughout childhood. Chronological age and Tanner‐Whitehouse II technique skeletal ages at 9 years were not significantly different between groups or between sexes within groups. Discussion: Because AGA children with rapid weight gain have a greater risk of overweight and obesity but are not advanced in skeletal maturity, later adolescent adjustments toward average weight and fatness values are unlikely. The identification and monitoring of such children is of importance in reducing their risk of morbidity.  相似文献   

9.
Age at menarche is associated with anthropometry in adolescence. Recently, there has been growing support for the hypothesis that timing of menarche may be set early in life but modified by changes in body size and composition in childhood. To evaluate this, a cohort of 255 girls aged <5 years recruited in 1988 were followed up in 2001 in Matlab, Bangladesh. The analysis was based on nutritional status as assessed by anthropometry and recalled age at menarche. Data were examined using lifetable techniques and the Cox regression model. The association between nutritional status indicators and age at menarche was examined in a multivariate model adjusting for potential confounding variables. Censored cases were accounted for. The median age at menarche was 15.1 years. After controlling for early-life predictors (birth size, childhood underweight, childhood stunting) it appeared that adolescent stunting stood out as the most important determinant of age at menarche. Adolescent stunting still resonates from the effect of stunting in early childhood (OR respectively 2.63 (p<0.01 CI: 1.32-5.24) and 8.47 (p<0.001 CI: 3.79-18.93) for moderately and severely stunted under-fives as compared with the reference category). Birth size was not a significant predictor of age at menarche. It is concluded that age at menarche is strongly influenced by nutritional status in adolescence, notably the level of stunting, which is in turn highly dependent on the level of stunting in early childhood. A 'late' menarche due to stunting may be detrimental for reproductive health in case of early childbearing because of the association between height and pelvic size.  相似文献   

10.
艾琼华 《人类学学报》1986,5(4):377-382
1983年7月至1984年7月,用回忆法调查了新疆伊犁地区3972名12—23岁的女性的初潮年龄,其中哈萨克族924人,维吾尔族864人,锡伯族486人,回族209人,蒙古族216人,汉族1273人。其平均初潮年龄是:哈萨克族14.37±1.09岁,维吾尔族14.34±1.41岁,蒙古族14.21±1.05岁,回族13.89±1.32岁,锡伯族13.78±1.02岁,汉族13.61±1.11岁。各族中均以七、八、九三个月来月经的最多。此外,还发现六个民族中1969—1972年出生的与1961—1964年出生的相比,平均初潮年龄都明显提前。在八年中,回族提前2.67岁,蒙古族提前1.90岁,锡伯族提前1.78岁,汉族提前1.64岁,哈萨克族提前1.17岁,维吾尔族提前1.13岁。  相似文献   

11.
Ample literature describes the history of the association between the advances in the health and wealth of people, and mortality rates, life expectancy and adult height. Twenty-nine German studies with n > 200 subjects published since 1848 on menarcheal age, were reanalyzed, and 101 studies from various other European and non-European countries. On average, mean age at menarche declined since the mid-19th century. Historic urban samples tended to decline earlier than rural groups, upper class women earlier than working class women. In Germany, minimum values for the age at menarche were seen already between the two World Wars (Leipzig 12.6 years in 1934, Halle 13.3 years in 1939). Values for mean age and SD for age at menarche were strongly associated. With improving historic circumstances, the two parameters declined in parallel. The standard deviation for menarcheal age dropped from over 2.5 years in mid-19" century France to little more or even less than 1 year in most modern countries. In the German studies the correlation between menarcheal age and SD was almost complete with r = 0.96 (y = 0.35x - 3.53). Similar associations between mean age at menarche and SD for age were found in other European countries. The obvious and immediate effects of historic events on menarcheal age, and particularly on the age distribution, indicate that menarche is a sensitive indicator of public health and wealth, and may be an appropriate estimator for the socio-economic background of historic populations.  相似文献   

12.
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   

13.
Data on the menarcheal age was collected from a sample of 749 girls, aged between 11 and 17 years of age, drawn from the population of Marrakech (Morocco). The mean age at menarche calculated for the entire sample was of 14.26 year of age (SD=1.20). Once having grouped the girls according to the different environmental factors, we calculated the mean menarcheal age for earch group. Comparisons of these means show that only the family size and the number of sibling have an effect on the age at menarche.  相似文献   

14.
Puberty, the transition from childhood to adult body size and sexual maturity, is a complex multi-staged process involving growth acceleration, weight gain and the appearance of secondary sexual physical features over a 2- to 3-year period. Recent genome-wide association (GWA) studies for age at menarche, the onset of the first menstrual period in girls, have identified the first common genetic variants to be robustly associated with pubertal timing. The findings indicate a novel link between microRNA pre-processing and the timing of whole organism growth and development. Our studies also demonstrate that the use of easily measured phenotypic markers, such as age at menarche in girls, in GWA studies can uncover genetic variants with wider relevance to more complex phenotypes, such as pubertal onset and the tempo of growth in both sexes.  相似文献   

15.
The data used in this work have been collected from clinical histories of women who have been examined at the Ginecology and Obstetritian Service of the Santa cruz y San Pablo Hospital of Barcelona. The sample consisted of 12,803 Spanish women, born between 1909 and 1965, by regions of birth. The method used is retrospective. The maximum menarcheal age in Spain (13.91±0.049 years) is found among those women born between 1925 and 1929 and the minimum menarcheal age (12.92±0.036 years) among women born between 1955 and 1959; so in an interval of 30 years, a reduction of almost a year (11.88 months) has taken place in age at first menstruation. This means a reduction of almost four months per decade. These differences are significant (p=.0000). The higher menarcheal age appears in the Northern Zone, due to the influence of Galicia in the sample (Galicia being a depressed zone with a great emigration rate). The earliest menarcheal age appears in the Mediterranean Zone due to the great percentage of catalan women (Catalonia being a region with a higher socioeconomical level). It is also to be observed that although the menarcheal age has decreased in all the zones, it has done so more dramatically in those zones which had higher values at the beginning. Although the secular trend of reduction in the age at menarche varies greatly from region to region, it may be considered that, in general, the socieconomic conditions have been the decisive factor in the change in physical maturation of Spanish women.  相似文献   

16.
Several studies have found relationships between early life factors (birth weight, length of gestation, height, weight, duration of breast-feeding, maternal age, social class, periods of infection, presence of adverse life events, and quality of housing conditions in childhood) and age at menarche but none has considered all of these factors in the same study. The follow-up study of the Newcastle Thousand Families birth cohort, established in 1947, provided age at menarche data collected retrospectively at age 50 from 276 women who returned self-completion questionnaires in 1997. Three main independent associations were observed: girls who experienced a shorter gestation, girls whose mothers were younger when they were born, and girls who were heavier at age 9 had earlier menarche. Birth weight, standardized for gestational age, was found to have different relationships with age at menarche depending upon how heavy or light a girl was at age 9. The results of this study support the hypotheses that conditions in fetal and early life are associated with the timing of menarche and that greater childhood growth is associated with earlier menarche. It is suggested that future work should focus on illuminating the mechanisms underlying these statistical relationships.  相似文献   

17.
Because humans have slow life histories, discussions of the optimal age at first birth have stressed the benefits of delayed reproduction. However, given the diversity of ecological, fertility, and mortality environments in which humans live, reproductive maturity is expected to be highly variable. This article uses reproductive histories to examine a pattern of early menarche and first birth among the Pume, a group of South American foragers. Age at menarche and first birth are constructed using both retrospective and cross‐sectional data for females over the age of 10 (n = 83). The objectives are first to define these patterns and then discuss their reproductive consequences. On average, Pume girls reach menarche at age 12.9, and give birth to their first child at age 15.3–15.5 (retrospective and cross‐sectional data, respectively). This populational average falls several years prior to what often is considered the human norm. Two questions are then considered. What are the infant mortality costs across a mother's reproductive career? How does surviving fertility vary with age at first birth? Results indicate that the youngest of first‐time mothers (<14) are four times more likely to loose their firstborns than older first‐time mothers (≥17). Given parity‐specific mortality rates, the optimal strategy to minimize infant mortality and maximize reproductive span is to initiate childbearing in the midteens. Women gain no additional advantage in surviving fertility by delaying childbearing until their late teens. Am J Phys Anthropol, 2008. © 2008 Wiley‐Liss, Inc.  相似文献   

18.
Early life factors are associated with the timing of reproductive events in adolescence, but a variety of hypotheses (such as psychosocial acceleration theory, paternal investment theory, extrinsic mortality, internal prediction, and intergenerational conflict) propose different explanations for why this may occur. To compare between these theories, we use the National Longitudinal Survey of Children and Youth, an extensive, longitudinal survey of Canadian male and female youth (aged 14-15 in last wave) to identify variables that uniquely support these different models (n≈1200). We identify the best predictors of sexual initiation for each hypothesis and then use a model selection procedure to determine which set of variables has the most support. Results show that variables representing extrinsic mortality cues, intergenerational conflict, early life psychosocial stressors, and prenatal factors are included in the top models, while variables representing social support and unpredictability are represented in some of the top models. Variables representing the paternal investment theory were not included in any of the top models, suggesting limited support for this hypothesis. These results support many of the hypotheses that have been previously presented in the literature, suggesting that timing of sexual initiation may have multiple causal pathways.  相似文献   

19.
Life history theory suggests that in risky and uncertain environments the optimal reproductive strategy is to reproduce early in order to maximize the probability of leaving any descendants at all. The fact that early menarche facilitates early reproduction provides an adaptationist rationale for our first two hypotheses: that women who experience more risky and uncertain environments early in life would have (1) earlier menarche and (2) earlier first births than women who experience less stress at an early age. Attachment theory and research provide the rationale for our second two hypotheses: that the subjective early experience of risky and uncertain environments (insecurity) is (3) part of an evolved mechanism for entraining alternative reproductive strategies contingent on environmental risk and uncertainty and (4) reflected in expected lifespan. Evidence from our pilot study of 100 women attending antenatal clinics at a large metropolitan hospital is consistent with all four hypotheses: Women reporting more troubled family relations early in life had earlier menarche, earlier first birth, were more likely to identify with insecure adult attachment styles, and expected shorter lifespans. Multivariate analyses show that early stress directly affected age at menarche and first birth, affected adult attachment in interaction with expected lifespan, but had no effect on expected lifespan, where its original effect was taken over by interactions between age at menarche and adult attachment as well as age at first birth and adult attachment. We discuss our results in terms of the need to combine evolutionary and developmental perspectives and the relation between early stress in general and father absence in particular. This work was supported by The University of Melbourne Department of Obstetrics and Gynaecology. James S. Chisholm is Professor in the School of Anatomy and Human Biology at the University of Western Australia. He is an anthropologist whose interests lie in the fields of human behavioral biology, evolutionary ecology, life history theory, and parental investment theory, where he focuses on infant social-emotional development, the development of reproductive strategies, and the integration of evolutionary, developmental, and cultural psychology and public health. Julie A. Quinlivan is Associate Professor in Obstetrics and Gynaecology at the University of Melbourne and Head of the Maternity Care Program at the Royal Women’s Hospital, Melbourne. Her interests are teenage pregnancy, domestic violence, child abuse prevention, and high-risk pregnancy. Rodney W. Petersen is Senior Lecturer in Obstetrics and Gynaecology at the University of Melbourne and Senior Consultant in Obstetrics and Gynaecology at the Royal Women’s Hospital and Sunshine Hospital in Melbourne. His interests are in psychosocial aspects of women’s health and cancer. David A. Coall is a Ph.D. student in the School of Anatomy and Human Biology at the University of Western Australia. His main interest lies in the application of evolutionary theory within an epidemiological framework. He is currently working on the synthesis of life history theory, parental investment theory, and parent-offspring conflict theory in exploring factors that influence variation in human birth weight and placental weight.  相似文献   

20.

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   

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