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Objective To investigate the possible associations between maternal pre-pregnancy body mass index (BMI) and daughters' age of menarche and subsequent markers of reproductive health. Methods Nine hundred eighty-five pregnant women (80 %) were enrolled at their routine 30th week examinations in 1988-1989. In 2008, a follow-up questionnaire was completed for 365 daughters (83 %), while 267 daughters (61 %) participated in a subsequent clinical examination. Main outcome measures were age of menarche, reproductive hormone profile, and ovarian follicle count in daughters. Results Daughters of mothers in the highest pre-pregnancy BMI tertile (BMI [greater than or equal to] 22.0 kg/m.sup.2) had an adjusted 4.1 (0.3; 8.0) months earlier menarche compared with the middle tertile group (BMI 20.0-21.9 kg/m.sup.2). Among non-users of hormonal contraceptives, daughters of mothers in the highest pre-pregnancy BMI tertile had non-significantly lower dehydroepiandrosterone-sulphate (DHEAS), estradiol, and free estrogen index (FEI), compared to the middle BMI tertile. This was supported by a sub-analysis using the WHO classification (underweight, BMI < 18.50; normal range, BMI 18.50-24.99; overweight/obese, BMI [greater than or equal to] 25.00 kg/m.sup.2) as exposure groups, in which daughters of overweight mothers had lower levels of DHEAS and estradiol, and lower FEI compared to daughters of normal weight mothers. No associations were found for ovarian follicle count in any of the groups. Conclusions for Practice We found that higher maternal BMI is associated with earlier age of menarche in daughters. A possible impact of maternal pre-pregnancy BMI on DHEAS and estradiol serum levels, and FEI in non-users of hormonal contraceptives was indicated, but the results were not statistically significant., Author(s): Saga Elise Mariansdatter[sup.1] [sup.2] , Andreas Ernst[sup.1] , Gunnar Toft[sup.2] [sup.3] , Sjurdur Frodi Olsen[sup.4] , Anne Vested[sup.2] , Susanne Lund Kristensen[sup.2] , Mette Lausten Hansen[sup.2] , Cecilia Høst [...]

Girls growing up in homes without their biological fathers tend to go through puberty earlier than their peers. Whereas evolutionary theories of socialization propose that this relation is causal, it could arise from environmental or genetic confounds. To distinguish between these competing explanations, the authors used a genetically and environmentally controlled sibling comparison design to examine the effects of differential exposure to family disruption/father absence in a community sample of sister pairs. As specified by evolutionary causal theories, younger sisters had earlier menarche than their older sisters in biologically disrupted families (n = 68) but not biologically intact families (n = 93). This effect was superseded, however, by a large moderating effect of paternal dysfunction. Younger sisters from disrupted families who were exposed to serious paternal dysfunction in early childhood attained menarche 11 months earlier than either their older sisters or other younger sisters from disrupted families who were not exposed to such dysfunction. These data suggest that early exposure to disordered paternal behavior, followed by family disruption and residential separation from the father, can lead to substantially earlier menarche. Keywords: evolutionary psychology, behavior genetics, father absence, father--child relations, divorce, puberty.

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 ([greater than or equal to] 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. KEY WORDS life history; age at first birth; menarche; infant mortality; hunter-gathers (foragers); Pume South American Indians

Menarche is the first menstrual period. It is the final event in the physical manifestation of gonadal development. A study in Europe found that the median age of menarche was 12 years and 11 months and that by the tenth year, 0.8% of the girls had their first menses, while the figure for the eleventh and twelfth years were 3.6 and 21.7% respectively. A Geneva study found that menarche was present in 50% at the age of 12.75 years. This study reported that, in the periods 1955-1980, the age of puberty has decreased by 0.5%, while the decrease between the periods 1965-1980 was 0.25%. Studies in the 70s and 80s found that African American girls were taller, heavier and maturing earlier than white girls of their age. Early menarche was observed in some of the girls by the age of 11 years, while all the girls were menstruating at the age of 15 years. Precocious puberty was defined as puberty before the age of eight years, while delayed puberty was defined as the absence of breast budding before the age of 14. However some pediatricians have concluded that the onset of breast development before the ages 7-8 years in white girls and between the ages of 6-7 years in African American girls may be part of the normal variation in the timing of puberty. It had been suspected that the decrease in the age of puberty is due to improved standard of living. However endocrine-disrupting chemicals from environmental pollutants are now seriously implicated as major factors in early puberty, while the ethnic factor has also been recognized. In this study, 489 students aged 15-17 selected from secondary schools from different areas of Trinidad were used. The data was collected through a questionnaire and the primary variable measured was the age of onset of menses. It also contained information on the ethnicity of the respondents. The heights and weights of the students were also measured. Results showed that, the mean age of menarche for Trinidadian girls was 11.71 years [+ or -]1.18. It also showed that the mean age for Blacks was 11.67 [+ or -]1.29, while that of Indians was 11.65 [+ or -]1.08. The mixed races' mean, was 11.87 [+ or -]1.09. No significant difference was found in the mean age of menarche between Blacks and East Indians. The result also showed a decrease in the age of menarche with increased BMI. The mean age of menarche of the mothers of the students sampled was 12.57 years, which is significantly higher that that of their daughters. This is consistent with recent findings, which reported that the mean age of menarche has been decreasing over the years in all societies. Key words: Mean age of menarche in Trinidad and Tobago, INTRODUCTION Menarche is the final event in a developmental process called puberty, which is a physical manifestation of the hormonal changes in the hypothalamic-pituitary-gonadal axis. The hypothalamic-pituitary-gonadal axis is minimally [...]

ABSTRACT Background Early menarche tends to be preceded by rapid infancy weight gain and is associated with increased childhood and adult obesity risk. As age at menarche is a heritable [...]

Girls who grow up in households with an unrelated adult male reach menarche earlier than peers, a finding hypothesized to be an evolutionary strategy for families under stress. The authors tested the alternative hypothesis that nonrandom selection into stepfathering due to shared environmental and/or genetic predispositions creates a spurious relation between stepfathering and early menarche. Using the unique controls for genetic and shared environmental experiences offered by the children-of-twins design, the authors found that cousins discordant for stepfathering did not differ in age of menarche. Moreover, controlling for mother's age of menarche eliminated differences in menarcheal age associated with stepfathering in unrelated girls. These findings strongly suggest selection, and not causation, accounts for the relationship between stepfathering and early menarche. Keywords: menarche, pubertal timing, family stress, children of twins, stepfathering

This study explored the information received about menstruation by Mexican women as well as their reactions to menarche. The most important topics that teenagers, young women, and middle-aged women were informed about were menstrual hygiene and physiology. In contrast, senior citizens were more informed about hygiene and activity restrictions. Regarding their reactions to menarche, teenagers and young women reported being confused. Positive reactions were reported only by older women who had knowledge about menstruation prior to menarche. Finally, younger women were more likely to present ambivalent reactions to menarche, probably because they are exposed to mixed messages which are often contradictory, resulting in more confusion and ambivalence. Keywords Menarche * Menstruation * Menstrual education

Menarche is the hallmark maturational event of female childhood. Many studies indicated a significant genetic contribution to the timing of the onset of menstruation, but most of these studies were limited by the use of retrospective data and by the use of data from only certain types of relatives (i.e., mothers and daughters, sisters, or twin sisters). The primary goal of this study was to use a modern maximum likelihood quantitative genetic method to estimate the heritability ([h.sup.2]) of age at menarche, using familial data collected over the course of the 74-year-old Fels Longitudinal Study. The secondary goal was to review earlier studies of the heritability of age at menarche. The study of the heritability of age at menarche presented here is unique for two reasons. First, because of the Fels Longitudinal Study's serial design, age-at-menarche data were collected prospectively from most participants. Second, because the Fels Longitudinal Study is a family study that has been conducted for decades, age-at-menarche data are available from many types of female relatives spanning multiple households and generations. The best-fitting and most parsimonious quantitative genetic model included provision for a secular decrease in age at menarche, and estimated the [h.sup.2] of age at menarche to be 0.49 [+ or -] 0.13 (95% confidence interval of [h.sup.2], = 0.24-0.73). The results of this study are in general agreement with the findings of most previous studies of genetic influences on age at menarche, and suggest that it is reasonable to consider it well-established that approximately half the phenotypic variation among girls from developed nations in the timing of menarche is due to genetic factors. Am J Phys Anthropol 128:210-219, 2005. KEY WORDS menarche; heritability; Fels Longitudinal Study

This paper reports on the findings of a focus group study that examines how women have experienced menarche at the personal level and in relation to the larger cultural, religious, and societal environment. Fifty-three women from 34 different countries were recruited in 13 focus groups. On the one hand, at the personal level, menarche stories shared in this study revealed salient themes concerning feelings experienced at the time of menarche, the importance of mother's reactions to their daughter's first menstruation, difficulties around understanding the meanings attached to menarche by others, managing menstrual products, as well as making sense of formal education related to menstruation, and the age of menarche. On the other hand, the discussions concerning how women experienced menarche in relation to the larger cultural, religious, and societal environment revealed secrecy to be a defining feature of many stories. Cultural expectations of learning, and following the rules and regulations surrounding menstruation led to different reactions in women at the time of their menarche. Very few women mentioned a ritual or celebration at the time of their menarche. Findings are discussed in terms of similarities and differences in menarche stories of women from different cultural backgrounds. Limitations of the study are mentioned and suggestions for future research are provided. Keywords: Menarche; Culture; Focus groups; Women's health

Resting metabolic rate (RMR) and body composition were measured in 44 initially nonoverweight girls at three time points relative to menarche: premenarche (Tanner stage 1 or 2), menarche ([+ or -] 6 mo), and 4 yr after menarche. Mean absolute RMR was 1,167, 1,418, and 1,347 kcal/day, respectively. Absolute RMR was statistically significantly higher at menarche than at 4 yr after menarche despite statistically significantly less fat-free mass (FFM) and fat mass (FM), suggesting an elevation in RMR around the time of menarche. The pattern of change in RMR, adjusted for FFM, log transformed FM, age, race, parental overweight, and two interactions (visit by parental overweight, parental overweight by FFM), was also considered. Adjusted RMR did not differ statistically between the visits for girls with two normal-weight parents. For girls with at least one overweight parent, adjusted RMR was statistically significantly lower 4 yr after menarche than at premenarche or menarche. Thus parental overweight may influence changes that occur in RMR during adolescence in girls. parental overweight; puberty; adolescence; obesity; energy expenditure

Perceptions of dieting amongst pre and postmenarchial female school students were studied.

Age at menarche has been examined in relation to family size and birth order in a sample of 895 girls from Bilbao, Spain, in the Basque region. Earlier menarche is associated with families of one child or four or more children, and with birth order of first or last, while the latest mean age of menarche occurs in girls of third birth order or those in families with three children.

The impact of sports training on the menstrual cycles of female athletes is affected by the age that training commenced and possibly the choice of sport. Female athletes who began training prior to the onset of menarche were more likely to experience oligo/amenorrhea, or nine or fewer cycles per year, than those who began after menarche. Sports selection may also be a factor, as premenarche athletes tend to participate in different sports than postmenarche athletes.

Retrospective data on age at menarche were collected for 832 Guatemalans 15-30 y in age to test whether exposure to a high energy and high protein supplement (Atole: 163 kcals/682 kJ and 11.5 g protein per cup or 180 mL) during childhood led to earlier menarche than did exposure to a low energy, no protein supplement (Fresco: 59 kcals/247 kJ in 180 mL). Mean age at menarche was similar in Atole (13.75 [+ or -] 1.22 y; mean [+ or -] SD) and Fresco (13.74 [+ or -] 1.36 y) groups. The corresponding value for immigrants (n = 144), subjects not exposed to the supplements, was 13.55 [+ or -] 1.20 y. Year of birth as well as socioeconomic status (SES) were associated with age at menarche. Age at menarche declined by 0.69 y over the 15-y period and menarche occurred earlier in higher SES households. Significant positive interactions between supplement type and SES and between supplement type and year of birth were found, but plausible explanations for them could not be advanced. INDEXING KEY WORDS: menarche; nutritional supplementation; secular change; Guatemala

The age of the onset of menstruation has been determined for the urban middle-class Cape Coloured population. From 1987 to 1992 data were collected from 857 girls aged 8 to 20 years attending primary and secondary schools in Cape Town. The schools were specifically selected for the highest socioeconomic status (SES) of pupils' parents. Three-quarters of parents fell into the higher three categories of the 5-category SES standard. Girls were interviewed with respect to their menarcheal status and those who were postmenarcheal were also asked to report when they had started to menstruate. The probit analysis of the status quo data yielded average of 12.61 years and a standard deviation (s) of 1.25 years. The retrospective method was applied only to recall data of 258 girls falling into fully postmenearcheal categories (16-20 years). It yielded an average of 12.75 (s = 1.32), insignificantly different from that obtained from the probit analysis. The menarcheal age of higher SES Cape Coloured girls is significantly lower than that of white girls in Cape Town (13.30 years) and much lower than that of any group of black South African girls. It falls close to the lower limit of the range reported worldwide. Body heights, weights, and Body Mass Index indicate good growth status of girls studied.

A longitudinal growth study is conducted to analyze the several methods that are employed to estimate the menarcheal age of women. The results obtained from such studies are found to be not enough satisfactory and hence needs to be coupled with other age corrections.

Retrospective data on menarcheal age and family composition were collected to better understand social influences on sexual maturation, and it was observed that absence of a biological father, the presence of half- and step-brothers and an urban environment are associated with early menarche. These findings suggest putative human pheromones that modulate sexual maturation to promote gene survival and prevent inbreeding, which occurs in rodents and nonhuman primates.

An estimated of 4,143 Mexican and Egyptian adolescents girls were studied to determine whether early age at menarche varied across body mass index (BMI), socioeconomic level, and urban rural residence. It was found that menarche at an earlier age was most strongly associated with overweight and obesity in both Mexican and Egyptian adolescents, while urban residence and high socioeconomic level were associated with Mexican adolescents only.

Objective. This study examines the relationship of intrauterine growth, measured by size and maturity at birth, to age at menarche, while also considering a wide range of other factors that may affect maturation. The research is motivated by the current debate about the importance of the prenatal environment as a determinant of later disease risk. Methods. Data were collected during the Cebu Longitudinal Health and Nutrition Survey. This community-based study has followed a cohort of several thousand Filipino infants since their birth in 1983 to 1984. Participants live in urban and rural communities of Metro Cebu, the second largest metropolitan area of the Philippines. The analysis sample includes 997 girls 14 to 15 years of age. The main outcome measure is age at menarche, determined from girls&apos; self-report of the month and year of first menses. Factors that influenced age at menarche were identified using Weibull parametric survival time models, The main exposure variables of interest included weight and length (measured by trained field staff) and gestational age (assessed from mother&apos;s reported date of last menstrual period, augmented by clinical assessments at birth). The analysis also takes into account a wide range of other factors that are likely to affect age at menarche. These include the girls&apos; early postnatal growth rates, premenarcheal body composition (body mass index and skinfold thicknesses measured at 8 years), current diet (measured by two 24-hour dietary recalls), and socioeconomic conditions of the household in which they live. We also assessed the contribution of maternal characteristics, including age at menarche, height, and nutritional status while pregnant with the study child. Results. The median age at menarche calculated from the hazard model is 13.1 years, with 50% of girls attaining menarche between 12.4 and 13.9 years. Earlier menarche is characteristic of girls who live in urban, higher socioeconomic status households, as indicated by higher maternal education, better housing quality, and possession of assets, such as a TV or refrigerator. Age at menarche is significantly associated with birth characteristics. Although birth weight alone was not significantly related to age at menarche, girls who were relatively long and thin at birth (>49 cm, Conclusions. The study provides additional evidence of fetal programming of later health outcomes by showing that future growth and maturation trajectories are established in utero. Furthermore, rapid postnatal growth potentiates the effects of size at birth and is related independently to earlier pubertal maturation. Pediatrics 2001;107(4). URL: http://www.pediatrics.org/ cgi/content/full/107/4/e59; birth weight, fetal programming, menarche.

The goals of this study were to assess the significance of two timing variables (objective timing of menarche and subjective timing, i.e., the belief -- not necessarily true -- about one's status as early, average, or late maturing) and two cognitive variables (preparation for menstruation and ego functioning) as predictors of the experience of menarche. Subjects were 92 girls who changed from pre- to postmenarcheal between two test occasions, six months apart. Findings were that subjective timing of menarche and preparation were significant predictors of menarcheal experience, while objective timing and ego functioning were not. The results replicated earlier findings based on cross-sectional analyses. Interpretation of the results suggested some directions for further exploration of determinants of initial menstrual experience.

In recent years, anecdotal evidence and limited survey research has suggested that the age of onset of sexual maturation has declined among girls in the Western world. However, an earlier [...]

Research was conducted to examine the age-at-menarche differential fecundity hypothesis. Focus was made on the entire reproductive life of early and late menarcheal women in Sudan in terms of their transition from one parity to the next. A sample of 3,115 women participated in the survey that was performed from Dec 1978 to Apr 1979. Results provide little evidence that early menarcheal women were more fund than their late puberty counterparts.