Age at menarche in a group of French schoolgirls

On-Field Methodological Approach to Monitor the Menstrual Cycle and Hormonal Phases in Elite Female Athletes

OBJECTIVES

Currently, there are no guidelines for implementing the monitoring of menstrual status, including the natural menstrual cycle (NC) or oral contraception (OC), in a sport setting. We aimed to provide a feasible, on-field methodological approach for monitoring NC and OC in female athletes.

METHODS

We developed a smartphone app with daily questionnaires to monitor both NC and OC phases in 19 elite female soccer players (23.7 [4.4] y) over 7 months. Adherence and compliance were evaluated. The NC and OC phases were based on calendar data to establish an individual menstrual profile for each athlete.

RESULTS

The initial questionnaire revealed that the vast majority of female players (80%) were interested in monitoring their menstrual status. The online monitoring yielded high athlete adherence (87.0% [14.2%]) with a slight decrease over the winter break and at the end of the championship, which necessitated adaptations to promote compliance. Monitoring identified the specific menstrual pattern of each athlete and highlighted large interindividual variability.

CONCLUSION

This study assesses, for the first time, the interest of female players in monitoring their menstrual status. It provides a new methodological approach, as well as guidelines for optimizing on-field monitoring. It also anticipates some obstacles sport staff may encounter when trying to implement such follow-up. It is essential to better understand the menstrual profile of athletes and determine its potential impacts on well-being and performance.

Spatio-temporal trends of the age-at-menarche percentiles among Portuguese women since 1920

BACKGROUND

This work aims to study the spatio-temporal evolution of a woman's age at menarche in the central region of Portugal. One of the concerns of the study is early or late menarches; thus, we consider percentile regression to build the respective curves as opposed to the more traditional mean regression approach.

METHODS

We analysed the data from [Formula: see text] women born in the period 1920-1973 who attended a free breast cancer screening program between 1990 and 2019. Distributional regression models inside the package GAMLSS in R were considered. These methods allowed us not only to model the location (mean) of the specific probability distribution of the age at menarche, but also allowed for the scale (variance) parameter of this distribution to depend on covariates. Additionally, a spatial random-effect was considered in order to capture the correlation at the regional level. The obtained clustered spatial effects were analysed to assess geographical differences among the percentiles of the age at menarche by year of birth.

RESULTS

A decreasing trend in the age at menarche (about 1.5 years in 5 decades) and regional differences for all the considered percentiles were found. Women living in the north-central areas of the central region of Portugal tend to have menarche at older ages.

CONCLUSION

We obtained percentile estimates for the age at menarche by year of birth and region of residence and demonstrated that these two explanatory variables have an impact on the explanation about the decreasing trend in age at a woman's first menstruation.

Growth in Infancy and Childhood and Age at Menarche in Five Low- or Middle-Income Countries: Consortium of Health Orientated Research in Transitional Societies (COHORTS)

BACKGROUND

Earlier age at menarche is associated with behavioral and noncommunicable disease risks. The influence of birth weight (BW) (intrauterine) and postnatal growth on age at menarche is not well studied in low- and middle-income countries (LMICs).

OBJECTIVE

Therefore, we investigated these associations in 5 LMIC birth cohorts.

METHODS

We analyzed data from Brazil, Guatemala, India, the Philippines, and South Africa (n = 3983). We derived stunting (< -2 SD scores) at 24 mo using the WHO child growth standards. We generated interaction terms with categorized BW and conditional weight (lighter < 0 or heavier ≥ 0), and height (shorter < 0 or taller ≥ 0) z-scores. We categorized early-, modal-, and late-onset menarche and used multilevel ordinal regression. We used multilevel linear regression on continuous age at menarche.

RESULTS

Mean age at menarche was 12.8 y (95% CI: 12.7 12.9). BW was not associated with age at menarche. Conditional height at 24 mo and mid-childhood (OR: 1.35; 95% CI: 1.27, 1.44 and 1.32; 1.25, 1.41, respectively) and conditional weight at 24 mo and mid-childhood (OR: 1.15; 1.08, 1.22 and 1.18; 1.11, 1.25, respectively) were associated with increased likelihood of early-onset menarche. Being heavier at birth and taller at 24 mo was associated with a 4-mo (95% CI: 0.8, 7.6) earlier age at menarche than being lighter at birth and shorter at 24 mo. Being heavier at birth but lighter in mid-childhood was associated with a 3-mo (95% CI: 0.8, 4.8) later age at menarche than being lighter at birth and mid-childhood. Age at menarche was 7 mo later in stunted than nonstunted girls.

CONCLUSION

Age at menarche is inversely related to relative weight gain but also to rapid linear growth among those born shorter but remained stunted, and those born taller and grew excessively. These findings do not deter the global health goal to reduce growth faltering but emphasize the potential adverse effects of an obesogenic environment on adolescent development.

Age at menarche and its association with blood pressure in adult women of developing countries: a systematic review and meta-analysis

CONTEXT

Evidence about the effect of age at menarche (AAM) on blood pressure (BP) has largely been drawn from studies in developed countries. Studies in developing countries are expanding recently but have not been summarised.

OBJECTIVE

To systematically explore the association between AAM and BP and the potential modifiers in developing countries.

METHODS

We searched PubMed, Embase, and Web of Science for publications until March 2022. A random-effects model was used to calculate the pooled relative risk (RR) with 95% confidence interval (CI).

RESULTS

Twenty studies were eligible. In studies with participants' mean age at BP assessment <55 years, women in the oldest group as compared with the middle or the youngest group of AAM had a higher risk of hypertension in those studies without adjustment for confounders (RR 1.79, 95% CI 1.41-2.28, I²=97.0%), those with adjustment for confounders excluding adiposity (1.25,1.04-1.51, I²=84.8%), and those with adjustment for confounders including adiposity (1.38,1.03-1.86, I²=91.8%). In studies with participants' mean age at BP assessment ≥55 years, no significant differences were found for studies without adjustment for confounders (RR 1.07, 95% CI 0.78-1.47, I²=90.3%), studies with adjustment for confounders excluding adiposity (0.85, 0.78-0.92, I²=12.3%), or studies with adjustment for confounders including adiposity (0.95, 0.80-1.11, I²=45.5%). A similar association was observed between AAM and baseline systolic BP and diabolic BP.

CONCLUSION

Late menarche was associated with a higher risk of BP and this association was modified by age and adiposity in developing countries.

Associations between Age at Menarche and Dietary Patterns with Blood Pressure in Southwestern Chinese Adults

The aim of our study was to examine the relationship between age at menarche (AM) and hypertension and to evaluate whether different dietary patterns have an effect on associations between AM and hypertension in a large-scale Han Chinese population in southwest China. A cross-sectional study was performed that included 44,900 participants from 17 districts in southwest China from September 2018 to January 2019. The study comprised 23,805 individuals in the final analysis. Logistic regression and multivariable linear regression were applied to estimate the dietary pattern-specific associations between AM and hypertension or systolic/diastolic blood pressure (SBP/DBP). Restricted cubic spline regression was utilized to calculate the shape of the relationship between AM and the odds ratio of hypertension. After adjusting for multiple variables, women who had a history of AM > 14 years were associated with an increased risk of hypertension (OR 1.12, 95%CI 1.04−1.19) and elevated levels of SBP (β 0.90, 95%CI 0.41−1.38) compared with those with AM ≤ 14 years among the total population, and this association was still statistically significant when we further adjusted for body mass index (BMI). In participants with AM > 14 years, the odds ratio values of hypertension increased with increasing menarche age. After stratification by age at recruitment, the positive association between menarche age and hypertension only remained in the middle-aged group, and this association was not found in the young and old groups. After stratification by the Dietary Approaches to Stop Hypertension (DASH) score among the total population, the positive association between AM and hypertension was presented only in the low DASH score group; however, this association was not found in the high DASH score group. Women who have a history of AM > 14 years should pay close attention to blood pressure levels and incorporate the DASH diet more in order to achieve the early prevention of hypertension, especially middle-aged women.

A secular trend in age at menarche in Yunnan Province, China: a multiethnic population study of 1,275,000 women

Background

Age at menarche (AAM) has shown different trends in women from different ethnic and economic regions in recent decades. Data on AAM among multiethnic women living in developing areas are scarce.

Methods

Data on AAM from 1,275,000 women among 26 ethnicities in Yunnan Province, China, who were born from 1965 to 2001 were obtained from the National Free Preconception Health Examination Project from 2010 to 2018. The patterns of AAM trends were analysed according to ethnic group, area of residence, and socioeconomic status.

Results

The mean AAM was 13.7 ± 1.21 years (95% CI 13.697–13.701), with a decrease from 14.12 (±1.41) among women born before 1970 to 13.3 (±1.04) among those born after 2000. The decline was 0.36 years per 10-year birth cohort, and the plateau has not yet been reached in Yunnan. A secular trend of earlier AAM was observed in all 26 ethnic groups. The fastest rate of decline was observed for the Bai ethnicity (0.36 years per decade). Consistent declining trends in AAM appeared among extreme-, middling-, and nonpoverty economic patterns from 1965 to 2001, with reductions of 1.19, 1.44, and 1.5 years, respectively (P < 0.001). The peak reduction among middling poverty and extreme poverty occurred in the early 2000s (0.4 and 0.32 years). Multivariate analysis showed a significant difference in the declining trends in AAM along rural/urban lines (P < 0.001).

Conclusion

There was a secular trend towards a younger AAM during the twentieth century and early twenty-first century birth cohorts in the Yunnan population. Considering the difference in AAM trends due to ethnic and socioeconomic status in Yunnan, the health authority should utilize flexible adjusted health care strategies in different regions.

Supplementary Information

The online version contains supplementary material available at 10.1186/s12889-021-11951-x.

Determination of thresholds of risk in women at average risk of breast cancer to personalize the organized screening program

In France, more than 10 million women at "average" risk of breast cancer (BC), are included in the organized BC screening. Existing predictive models of BC risk are not adapted to the French population. Thus, we set up a new score in the French Hérault region and looked for subgroups at a graded level of risk in women at "average" risk. We recruited a retrospective cohort of women, aged 50 to 60, who underwent the organized BC screening, and included 2241 non-cancer women and 527 who developed a BC during a 12-year follow-up period (2006-2018). The risk factors identified were high breast density (ACR BI-RADS grading)(B vs A: HR = 1.41, 95%CI [1.05; 1.9], p = 0.023; C vs A: HR = 1.65 [1.2; 2.27], p = 0.02 ; D vs A: HR = 2.11 [1.25;3.58], p = 0.006), a history of maternal breast cancer (HR = 1.61 [1.24; 2.09], p < 0.001), and socioeconomic difficulties (HR 1.23 [1.09; 1.55], p = 0.003). While early menopause (HR = 0.36 [0.13; 0.99], p = 0.003) and an age at menarche after 12 years (HR = 0.77 [0.63; 0.95], p = 0.047) were protective factors. We identified 3 groups at risk: lower, average, and higher, respectively. A low threshold was characterized at 1.9% of 12-year risk and a high threshold at 4.5% 12-year risk. Mean 12-year risks in the 3 groups of risk were 1.37%, 2.68%, and 5.84%, respectively. Thus, 12% of women presented a level of risk different from the average risk group, corresponding to 600,000 women involved in the French organized BC screening, enabling to propose a new strategy to personalize the national BC screening. On one hand, for women at lower risk, we proposed to reduce the frequency of mammograms and on the other hand, for women at higher risk, we suggested intensifying surveillance.

Age at menarche and risk of hypertension in Chinese adult women: Results from a large representative nationwide population

This study explored the association between age at menarche and the risk of hypertension in Chinese women. A total of 234 867 women aged ≥18 years from the China Hypertension Survey were included in this study. Participants were required to complete a standard questionnaire. Blood pressure and physical examination of the participants were performed by trained medical staff. Spearman correlation analysis was used to explore the correlation between age at menarche and other individual characteristics. Logistic regression was used to estimate the odds ratios for hypertension by age in years at menarche. The average age at menarche in Chinese women was 14.8 years. Women who were older at menarche were more likely to have a higher body mass index, larger waist circumference, smoke, and have a primary education (p < .05). After adjustments, odds ratios (95% confidence interval) for hypertension across age at menarche groups were 0.912 (0.877-0.948), 0.927 (0.893-0.963), 1.00 (reference), 1.061 (1.020-1.102), and 1.129 (1.090-1.169) for those aged ≤13, 14, 15 (reference), 16, and ≥17 years at menarche, respectively. Each 1-year delay in menarche was associated with a 6.2% increase in the prevalence of hypertension (odds ratio, 1.062; 95% confidence interval, 1.053-1.071). The positive association between age at menarche and hypertension was evident among age at recruitment groups, BMI categories, and education levels. This association was stronger in urban women and postmenopausal women. Our findings suggest that late menarche is related to a higher risk of hypertension among Chinese adult women, and this association appeared similar among different subgroups.

Association between factors related to the pregnancy, neonatal period, and later complications (especially asthma) and menarcheal age in a sample of Lebanese girls

BACKGROUND

Studies about the majority of the factors that may potentially influence the pubertal timing and menarche were controversial. The objective was to evaluate the association between factors related to the pregnancy, neonatal period, and the complications that may happen later in life and the menarcheal age in a sample of Lebanese girls admitted or not to the NICU at birth. Our secondary objective was to try to find, for the first time in literature, a correlation between respiratory distress at birth and the need of oxygen therapy with the age of the first menses in these girls.

METHODS

It is a cross-sectional retrospective study, conducted between January and March 2019. Our sample included all the 2474 girls born in Notre-Dame-de-Secours hospital, between 2000 and 2005; the sample consisted of 297 girls (97 girls admitted to the NICU and 200 randomly chosen to participate in our study with a ratio of 1:2 (1 girl admitted to the NICU vs 2 girls born in the nursery).

RESULTS

Asthma later in life was significantly associated with lower age at menarche in girls, whereas a higher mother's age at menarche and a higher gestational age were significantly associated with higher age at menarche in girls. When taking each cause of NICU admission as an independent variable, showed that a higher mother's age at menarche was significantly associated with higher age at menarche in girls, whereas a higher number of days of phototherapy, a preeclampsia in the mother during pregnancy and asthma later in life in the girl were significantly associated with a lower age at menarche in girls.

CONCLUSION

The timing of menarche seems to be associated with many factors in Lebanese girls that should not be disregarded by physicians.

The levelling-off of the secular trend of age at menarche among Italian girls

OBJECTIVE

The main aim of this study was to verify whether the secular trend stopped in Italy by comparing the results of a 1990-2000 birth cohort versus a 1980-1990 birth cohort of Italian young women. The results were used to speculate about age at menarche as adaptive response to non-genetic factors.

METHODS

In 2016, a study was set on 413, 18-to-26 year-old women (1990-2000 birth cohort) attending two Italian Universities by web-based, self-reported questionnaires. Previously in 2000, a research including 3,783 high school female students (1980-1990 birth cohort) was led. The age at menarche distribution was performed by Kaplan-Meier analysis. The comparison between the findings of the two birth cohorts was performed by Wilcoxon sum-rank test. Mixed models analysis was applied to evaluate the effect of cohort and socio-economic status on age at menarche.

RESULTS

1990-2000 cohort's age at menarche median was 12.44y (95%CI 12.37; 12.59y). There was no significant difference with age at menarche of the previous cohort (p = 0.56). Consistently, the advance of age at menarche in comparison to the mothers' one was not significantly different between the two cohorts (-0.27y±0.10y vs -0.25y±0.03y, p = 0.33). The socio-economic level was not significantly associated with menarcheal age.

CONCLUSIONS

The findings of this study confirm that, like in other developed countries, the advance of age at menarche has stopped in Italy, consistently with the stop of the improvement of socio-economic conditions. Further studies are needed to explore the differential effect of each non-genetic factor to outline future scenarios of human sexual maturation.

TRIAL REGISTRATION

the Comitato Etico per la Sperimentazione Clinica (CESC) della Provincia di Padova of the Veneto Region (Italy), n°3993/U16/16.

Somatic profile in lung cancers is associated to reproductive factors in never-smokers women: Results from the IFCT-1002 BioCAST study

BACKGROUND

Lung cancer in women is on the rise, with a higher proportion occurring in lifelong never-smokers. Lung cancer in never-smokers (LCINS) exhibits a high frequency of driver oncogene alterations. In this study, we aimed to investigate whether exposure to reproductive factors in women with LCINS may modulate the molecular pattern.

METHODS

All newly diagnosed LCINSs were included in a prospective, observational study (IFCT-1002 BioCAST). Each patient responded to a questionnaire including reproductive factors. Biomarker test results were also collected.

RESULTS

Two hundred and sixty women were included in this analysis, and 166 alterations were characterized. EGFR mutation frequency proved greater among patients with late menarche (74% in age>14 vs. 40% and 41% for 12-14 and ≤12 years, respectively; P=0.020) and tended to decrease with increasingly late age at menopause. In multivariate analysis, EGFR mutation frequency increased by 23% per increment of 1 year of age at menarche (P=0.048), and by 9% for each year at age at first birth (P=0.035). ALK alteration frequency was greater in women with high parity (50% in≥5 vs. 12% and 7% for 1-4 and nulliparity, respectively; P=0.021).

CONCLUSION

In a cohort of women LCINSs, female hormonal factors appear to impact molecular pattern.

Age at menarche, menstrual characteristics, and its associated morbidities among secondary school students in Abakaliki, southeast Nigeria

BACKGROUND

Menstruation has a variable pattern. Knowledge of age at menarche and providing accurate information to adolescent girls is necessary to allay anxiety, treat menstrual morbidities, and improve their quality of life.

OBJECTIVE

To determine the age at menarche and menstrual characteristics of adolescent secondary school girls in Abakaliki.

MATERIALS AND METHODS

A cross-sectional descriptive study was conducted in seven secondary schools in Abakaliki among 960 female students. A total of 450 girls were randomly selected for the study. A pretested self-administered questionnaire was used in data collection. Four hundred questionnaires were properly filled and used for the final analysis.

RESULTS

The age range of the students was between 10 - 21years. The mean age of the respondents was 16.2 ± 1.7years. The average age at menarche was 13 ± 1.0 years. Urban dwellers had menarche 0.2years earlier than rural dwellers. There is an association between menarche and social class (X [2] 372.9 (2), p = 0.001). About 87.75% of the respondents had an average cycle length. Most (88.3%) of the respondents had a menstrual flow duration of 3-5 days. Dysmenorrhoea was present in 82% of respondents and was severe enough to cause absence from school in 56.5% of students. Oligomenorrhea and menorrhagia occurred in 8.5 % and 6.25 % of the student studied. Mothers (80.0%), friends (75.0%) and teachers (74.5%) accounted for the bulk of the information on menstrual health.

CONCLUSION

The average age at menarche was 13 ± 1.0 years. Dysmenorrhea is a major cause of morbidity amongst this age group and should be empathically addressed. It is therefore important that the students, their parents, and school managers in the study area be educated on the issues of menstrual problems that can occur in an adolescent.

Age at Menarche in Women With Bipolar Disorder: Correlation With Clinical Features and Peripartum Episodes

BACKGROUND

Bipolar disorder (BD) is related to reproductive cycles. However, findings on putative correlation between age at menarche and course of BD are particularly scarce and conflicting. The aim of the present study is to analyze the relationship between age at menarche and characteristics of BD, including comorbid medical conditions and peripartum mood episodes.

METHODS

The study sample consists of 288 women with BD type I, II, or not otherwise specified (NOS). Age at menarche was both considered as a continuous variable and categorized into three groups: early menarche (≤11 years), normal menarche (12-14 years), and late menarche (≥15 years). The study focused on two sets of comparisons, by age at menarche and women with vs. without children. Spearman correlation matrix was produced to calculate correlations between the variables of interest. Socio-demographic and clinical characteristics between early, normal and late menarche, and women with vs. without children were examined through descriptive statistics. Finally, adjusted logistic regression analysis was run to examine the association between variables.

RESULTS

Out of 288 women included in the study, 21.5% had early menarche, 55.6% had normal, and 22.9% had late menarche. Women with early menarche had higher rates of metabolic syndrome compared to women with normal menarche even after adjustment for age. The subgroup of women with children does not present clinical differences compared to women without children except a lower rate of psychiatric comorbidities. At least one mood episode with peripartum onset occurred in 29.6% of the women with children. After controlling for confounding variables, women with late menarche were associated with lower probability of BD peripartum episodes compared to women with normal menarche.

CONCLUSION

Age at menarche may be related to specific characteristics of women with BD. The results deserve to be deepened in further studies.

The relationship among the age at menarche, anthropometric characteristics, and socio-economic factors in Bengali girls from Kolkata, India

OBJECTIVES

The aim of the study was to measure the causal effect of selected socio-economic factors and anthropometrical characteristics on the menarche occurrence.

METHODS

The sample consisted of 2195 Bengali girls (aged 7-21) from middle-class families, from Kolkata city, India. The age at menarche was recorded from the retrospective data and status quo method. The causal effect of anthropometric and socio-economic variables on menarche occurrence was estimated by the nonparametrical analysis of survival probability (survival random forest).

RESULTS

In the examined cohort menarche occurred, on average, at 11.8 years of age. The probability of menarche occurrence amplified with the increasing values of factors such as body mass index, height-for-age z-scores, number of family members, household rooms, and toilets, but decreased when expenditures increased. The relation maintained a similar pattern of causal effect with girls' age.

CONCLUSIONS

A complex pattern of relationship among sexual development, physique, and socio-economic characteristics was defined. The tendency toward early menarche, along with the observed causal relationships indicate that the analyzed sample is nearing the characteristics and standards of living noted in other middle and even high-income countries in the world.

Genital tract and reproductive characteristics in daughters of women and men prenatally exposed to diethylstilbestrol (DES)

OBJECTIVE

Prenatal exposure of women to diethylstilbestrol (DES) has been associated with reproductive tract anomalies, menstrual irregularity, infertility and pregnancy complications. In prenatally exposed men, adverse effects included genital anomalies and possible risk of infertility. In children of prenatally exposed women, i.e the third generation, an increased incidence of genital defects was observed in sons (hypospadias), but not in daughters. In daughters of prenatally exposed men, the incidence of genital anomalies was in the normal range. Experimental studies in mice evidenced an increased incidence of reproductive tract anomalies in the female descendants of females and males prenatally exposed to DES, indicative of transgenerational transmission of DES defects. The aim of this study is to assess genital tract defects, fertility and pregnancy outcome, in daughters of women and men prenatally exposed to DES.

METHODS

In a retrospective observational analysis, 759 daughters of prenatally exposed women and men reported their genital and reproductive characteristics that were compared with those of: 1) general population in France; 2) two cohorts of daughters of exposed women reported in previous publications; 3) women prenatally exposed to DES.

RESULTS

An increased incidence of uterine defects was observed, with both doubling of uterus and bicornuate and aplastic uterus which constitutes the Mayer-Rokitansky-Küster-Hauser syndrome (MRKHS). No specific anomalies described in prenatally exposed women such as T-shape or hypoplastic uterus were reported. Infertility appeared to be in the normal range. Pregnancy outcomes of our 121 pregnancies of women born to DES exposed mothers and two other published cohorts presented inconsistent results for ectopic pregnancy, miscarriage and preterm delivery. Early and late miscarriages were higher than expected in general population in our cohort but not in the two others.

CONCLUSION

These results must be considered as preliminary, due to the small numbers of patients, limited follow-up duration after birth due to young age of the studied population, and observational methods. An important point is that the high risk of reproductive dysfunction of women prenatally exposed to DES was not observed in their daughters. There is a signal on the high incidence of uterine defects, especially aplastic uterus, and its possible link with DES exposure through epigenetic effects is discussed in our findings. Inconsistent findings regarding pregnancy outcomes in the third generation are worthy of further examination.

Association between Age at Menarche and Hypertension among Females in Southern China: A Cross-Sectional Study

Background

Association between age at menarche (AAM) and hypertension remains a controversial topic, and data in China were sparse. Therefore, we aimed to investigate the association between AAM and hypertension in Chinese female population.

Methods

In this cross-sectional study, 5,102 females aged ≥15 years were enrolled. Self-reported AAM was assessed by the questionnaire. Multiple linear regression analysis was used to evaluate the association between systolic blood pressure (SBP), diastolic blood pressure (DBP), and AAM. Logistic regression analysis was performed to evaluate the association between hypertension and AAM. Generalized additive model (GAM) and smooth curve fitting (penalized spline method) were conducted to explore the exact shape of curve between them.

Results

The overall mean of AAM was 15.5 years. Each additional year of AAM was associated with a 15% higher risk of hypertension (odds ratio (OR) = 1.15, 95% confidence interval (CI): 1.11-1.19). Among females with hypertension, there was a significant positive association between AAM and SBP (β = 0.88, 95% CI: 0.29-1.46) and DBP (β = 0.80, 95% CI: 0.47-1.13). A significantly higher risk of hypertension was found in younger subjects (15-44 y: OR = 1.37, 95% CI: 1.21-1.55; P for interaction = 0.009) compared with those aged between 62 and 97 y.

Conclusions

AAM was positively associated with hypertension and blood pressure, especially among females in early adulthood from southern China.

Is menarche occuring earlier among Lebanese girls?

BACKGROUND

Early menarche is associated with increased risks for several diseases such as cardiovascular diseases and breast cancer. This analysis aimed at generating evidence on a historical trend towards younger age at menarche among Lebanese girls.

METHODS

A secondary analysis was conducted on data consolidated from three serial cross-sectional national surveys of women in Lebanon (2007, 2009 and 2012). A total of 6150 women were included in order to study the association between date of birth intervals and age at menarche.

RESULTS

The mean age at menarche was 13.06 years, with a peak of the distribution at age 12. Women born before 1950 had a significantly higher mean age at menarche (13.21) compared to those born in 1970 and thereafter (12.95). A stratified analysis showed that women living outside the metropolitan Greater Beirut (GB) area were characterized by an older mean age at menarche (13.11) in all date of birth intervals compared to those in GB (12.89). However, age at menarche declined more significantly over the last two decades among women outside GB, compared to those living in GB.

CONCLUSIONS

Epidemiological figures emerging from this study confirm that trends in Lebanon are in line with a global pattern of decreasing age at menarche. Urban-rural differences suggest that higher caloric content of diet and consequent early overweight, more evident in urban areas, are likely determinants of younger menarche. Evidence from this study calls for an urgent implementation of comprehensive multisectoral obesity prevention in children in Lebanon.

Timing of spermarche and menarche among urban students in Guangzhou, China: trends from 2005 to 2012 and association with Obesity

In Guangzhou, China, whether the trend of a decreasing pubertal age has continued in recent years remained unknown, and the association between obesity and early puberty was still controversial. Herein, we conducted a serial cross-sectional study using data from physical fitness surveillance (2005–2012), to determine the recent trends in age at spermarche and menarche among students in Guangzhou, and to investigate whether elevated BMI modified timing of spermarche and menarche. This study included 1,278,258 urban students. In boys, no significant differences were observed in median ages of spermarche (MAS) from 2005 to 2012, with overlapping 95% CIs. Similar results were observed for median ages of menarche (MAM) in girls. The Cox-Stuart trend test showed neither upward nor downward shift in MAS and MAM over time (P = 0.625; 1.000). Each year, both MAS and MAM decreased with increasing BMI. Furthermore, a higher BMI was associated with early age at spermarche and menarche, with ORs of 1.052 (95% CI = 1.045–1.059) and 1.233 (95% CI = 1.220–1.247) in 2012 for boys and girls, respectively. In conclusion, the pubertal timing has been stable in urban students from 2005 to 2012. Furthermore, obesity was associated with early timing of spermarche and menarche.

Age at menarche predicts age at onset of major affective and anxiety disorders

BACKGROUND

Menarche age has been associated inconsistently with the occurrence, timing or severity of major depressive disorder (MDD), but rarely studied in women with bipolar (BDs) or anxiety disorders.

METHODS

We investigated women patients at a Sardinian mood disorder center for associations of age at menarche with age at illness onset for major affective or anxiety disorders, year of birth, and other selected factors, using bivariate comparisons and multivariate regression modeling.

RESULTS

Among women (n=1139) with DSM-IV MDD (n=557), BD-I (n=223), BD-II (n=178), or anxiety disorders (n=181), born in 1904-1998, of mean age 42.9 years, menarche age averaged 12.8 [CI: 12.7-12.9] years. Illness onset age averaged 30.9 [30.1-31.8] years, ranking: BD-I, 25.8; anxiety disorders, 28.0; BD-II, 30.3; MDD, 34.1 years. Menarche age declined secularly over birth years, and was associated with younger illness-onset, having no or fewer siblings, more psychiatrically ill first-degree relatives, living in rural environments, being suicidal, substance abuse, and being unemployed. Earlier menarche and earlier illness-onset were significantly associated for onset age groups of ≤ 20, 20-39, and > 40 years. Menarche age versus diagnosis ranked: BD-II<BD-I<anxiety disorders<MDD.

CONCLUSIONS

Age at menarche in Sardinia, as elsewhere, has declined over the past decades. It was strongly associated with age at onset of bipolar and anxiety, as well as major depressive disorders across the age range, suggesting sustained effects of biological maturational factors.

The Evolution of the Age at Menarche from Prehistorical to Modern Times

Menarche denotes the onset of the female reproductive capacity. The age that menarche occurs is mostly attributed to the interaction of genetics and various environmental factors. Herein, the author describes the evolution of the age at menarche from prehistoric to the present times. Data from skeletal remains suggest that in the Paleolithic woman menarche occurred at an age between 7 and 13 years, early sexual maturation being a trade-off for reduced life expectancy. In the classical, as well as in the medieval years, the age at menarche was generally reported to be at approximately 14 years, with a range from 12 to 15 years. A significant retardation of the age at menarche occurred in the beginning of the modern times, soon after the industrial revolution, due to the deterioration of the living conditions, with most studies reporting menarche to occur at 15-16 years. In the 20th century, especially in the second half of it, in the industrialized countries, the age at menarche decreased significantly, as a result of the improvement of the socioeconomic conditions, occurring at 12-13 years. In the present times, in the developed countries, this trend seems to slow down or level off.

Secular trends in age at menarche among women born between 1955 and 1985 in Southeastern China

Background

Improvements in socioeconomic conditions and population health have been linked to declining age at menarche. In China, secular trends in age at menarche following extensive economic reform during recent decades have not been thoroughly investigated. This study examined the overall trend in age at menarche and assessed differences in the rate of change of age at menarche over time, and between urban and rural populations and education levels in southeastern China.

Methods

Age at menarche was retrospectively collected from 1,167,119 Han Chinese women born 1955–1985, who registered in the Perinatal Health Care Surveillance System in 19 cities and counties in two southeast provinces during 1993–2005. Multivariable linear regression was used to estimate trends in age at menarche overall and stratified by urban/rural residence and education level.

Results

Age at menarche declined by 0.33 [95% CI 0.33, 0.32] years/decade overall, with the fastest decline in women born in 1966–1975. For the earliest birth cohorts (1955–1965), age at menarche declined faster in urban versus rural regions, and for women with high school education or above versus primary school or less. In contrast, age at menarche declined slower among urban women born 1976–1985, and among those with higher education born 1966–1985.

Conclusions

Mean age at menarche declined for women born in 1955–1985 in southeast China. Further study is warranted to identify specific factors contributing to earlier age at menarche and associated health outcomes.

Electronic supplementary material

The online version of this article (doi:10.1186/s12905-014-0155-0) contains supplementary material, which is available to authorized users.