Update on age at menarche in Italy: toward the leveling off of the secular trend

A Century of Change: Unraveling the Impact of Socioeconomic/Historical Milestones on Age at Menarche and Other Female Reproductive Factors in Japan

BACKGROUND

Reproductive factors, such as age at menarche, are known to be associated with disease risk, but data on trends in these factors in Japan are limited. In this study, we investigated secular trends in reproductive factors and explored their potential association with socioeconomic and historical events.

METHODS

We conducted a retrospective analysis of 62,005 Japanese women born between 1890 and 1991 using a survey conducted over 25 years. Trends in reproductive factors were analyzed using linear and joinpoint regression models, and their associations with major historical events involving Japan were evaluated.

RESULTS

We found that the age at menarche showed a significant downward trend (P < 0.001) over the century. Three joinpoints were identified, in 1932 (15.23 years old), 1946 (13.48 years old), and 1959 (12.71 years old), which indicated that average age at menarche decreased by approximately 0.8% per year between 1932 and 1946, and then by 0.4% per year between 1946 and 1959, both of which were statistically significant. However, after 1959, age of menarche remained stable. Analyses of other reproductive factors found significant changes, including a decrease in parity and the number of babies breastfed, and an increase in age at first birth.

CONCLUSION

Age at menarche showed a long-term downward trend in Japan, with significant change points in annual percent change. Other factors showed secular changes in trends as well. These change points were observed at the same time as historical events, namely wars and economic development, suggesting that socioeconomic and environmental changes at the population level affect reproductive factors in females.

Temporal trend of age at menarche in Korean females born between 1927 and 2004: a population-based study

Backgrounds

The age at menarche has decreased worldwide. Previous studies on Korean adolescents have reported a downward trend in age at menarche. This study aimed to investigate the current trends in age at menarche among Korean adolescents using nationally representative data.

Materials and methods

The study used data from the Korea National Health and Nutrition Examination Survey 2007-2021. A total of 50,730 females born between 1927 and 2004 with information on age at menarche were included. The trend in age at menarche was analyzed according to 15 birth-year groups (with 5-year intervals) using quantile regression analysis.

Results

The mean age at menarche decreased from 16.92 ± 0.06 years for females born before 1935 to 12.45 ± 0.04 years for females born between 2000 and 2004 (p <.001). According to the percentile group of age at menarche, mean menarche age decreased by -0.071 years per year (95% confidence interval [CI], -0.072 to -0.070) in total, -0.050 years per year (95% CI, -0.052 to -0.048) in the 3rd percentile group, -0.088 years per year (95% CI, -0.091 to -0.085) in the 97th percentile group (p <.001 for all). A decreasing trend of age at menarche was more prominent in the obesity group (-0.080 years per year, 95% CI, -0.082 to -0.078) compared to the non-obesity group (-0.069 years per year, 95% CI, -0.071 to -0.068) (p <.001 for both).

Conclusion

Ongoing downward trend in age at menarche was observed in Korean females born until 2004, decreasing by 0.71 years per decade. The downward trend was faster in individuals with a higher percentile of age at menarche and in those with obesity.

Characterization of Puberty in an Australian Population-Based Cohort Study

PURPOSE

Current knowledge of the characteristics of puberty beyond age at menarche and thelarche is limited, particularly within population-based cohorts. Secular trends and concerns of the health effects of early puberty reinforce the value of contemporary studies characterizing the timing, tempo, duration, and synchronicity of puberty.

METHODS

The Childhood to Adolescence Transition Study is a unique Australian cohort of individuals followed annually from late childhood to late adolescence, with up to eight assessments of pubertal stage from 9 to 19 years of age (N = 1,183; 636 females). At each assessment, females reported their Tanner Stage of breast and pubic hair development, while males reported on genital/pubic hair development. Nonlinear mixed-effects models characterized pubertal trajectories and were used to derive each individual's estimates of timing, tempo, and synchronicity. Parametric survival models were used to estimate the overall duration of puberty.

RESULTS

Timing of mid-puberty (Tanner Stage 3) ranged from 12.5 to 13.5 years, with females developing approximately 6 months before males. Pubertal tempo (at mid-puberty) was similar across sex (between half and one Tanner Stage per year), but the overall duration of puberty was slightly shorter in males. Most females exhibited asynchronous changes of breast and pubic hair development.

DISCUSSION

Estimates of pubertal timing and tempo are consistent with reports of cohorts from two or more decades ago, suggesting stabilization of certain pubertal characteristics in predominantly White populations. However, our understanding of the duration of puberty and individual differences in pubertal characteristics (e.g., synchronicity of physical changes) remains limited.

Secular trends and urban-rural disparities in the median age at menarche among Chinese han girls from 1985 to 2019

BACKGROUND

Menarche is a substantial milestone of female puberty. Timing of age at menarche is considered the key to understanding the potential linkages with women's health outcomes later in life. This study aimed to explore the secular trends and urban‒rural disparities in the median age at menarche among Chinese Han girls from 1985 to 2019.

METHODS

Data were extracted from the 1985, 1995, 2005, 2014, and 2019 Chinese National Surveys on Students' Constitution and Health, which were nationally representative cross-sectional studies, and a total of 173,535 Han girls aged 9-18 years were examined. Girls were asked whether menarche had occurred. The median age at menarche was estimated by probit analysis. Z tests were used to compare the differences between survey years and between urban and rural areas.

RESULTS

The median age at menarche among Chinese Han girls decreased from 13.37 years in 1985 to 12.00 years in 2019, and the overall decrease was more significant in rural areas (1.77 years) than in urban areas (0.99 years). The average five-year change in the decrease in the median age at menarche showed an accelerating and then slowing pace; and it was observed similarly in both urban and rural areas. The urban‒rural disparities shrank from 0.64 years in 1985 to 0.44 years in 1995, then to 0.27 years in 2005, 0.24 years in 2014, and finally to - 0.14 years in 2019.

CONCLUSIONS

The median age at menarche among Chinese Han girls continued to decline from 1985 to 2019 but at a slowing pace in the last five years. Urban‒rural disparities gradually narrowed. Sexual and reproductive health education and interventions to prevent the decline in the age of menarche are needed, especially in rural areas.

Growth Velocity in South Indian Children Between Three and 18 Years of Age

Objective Height velocity is a crucial anthropometric parameter for the evaluation of mild- or recent-onset short stature; however, there is no data on height velocity in South Indian children. We undertook this study to establish the normative data. Methods This prospective longitudinal study included 3327 apparently healthy children aged three to 18 years from government and private schools of Krishna district, Andhra Pradesh. Height and weight were measured at baseline and three-monthly intervals for one year (October 2018 to October 2019). Results Age- and sex-specific height velocity percentiles were generated. The data was available in 1627 boys and 1700 girls. The mean peak height velocity (PHV) was 7.18±2.56 cm in boys observed at 12-12.9 years and 5.8±2.56 cm in girls at 10-10.9 years. Conclusion Normative height velocity data for South Indian children has been presented.

Age at menarche of adolescent girls and the neighbourhood socioeconomic status of their school area

PURPOSE

To assess the association between abnormal timing of menarche among adolescent girls and neighbourhood socioeconomic status of their school area.

MATERIALS AND METHODS

Our analysis included 187,024 girls aged 15-18 years from the Korea Youth Risk Behaviour Web-Based Survey (KYRBS) from 2007 to 2015. Early and late menarche were defined as menarche before 11 years and no menarche by age 14 years, respectively. The deprivation index values for the areas where the schools were located were used as an indicator of neighbourhood socioeconomic status based on the 2005 national census data. We calculated odds ratios (OR) for early and late menarche using a multinomial logistic regression model. Covariates included body mass index, parental education, single or stepparents, siblings, household wealth, year of birth, survey year, and urbanisation.

RESULTS

Mean age at menarche was 12 years. The overall proportions of early and late menarche were 11.3% and 3.3%, respectively. When divided into four quartile groups based on the socioeconomic deprivation index, 11.3% of girls in the most deprived quartile and 10.6% in the least deprived area showed early menarche. The prevalence of late menarche did not differ across the deprivation index quartiles of school area. Attendance at schools located in highly deprived areas was associated with up to 10% higher risk of early menarche. This positive association was not evident for late menarche.

CONCLUSION

Among contemporary Korean girls, socioeconomic deprivation of the school area was associated with earlier puberty. This finding highlights the potential role of the socioeconomic environment of schools in women's lifetime health.

Ongoing increasing trends in central precocious puberty incidence among Korean boys and girls from 2008 to 2020

BACKGROUND

Over the last few decades, there has been growing evidence of earlier onset and progression of puberty worldwide. This population-based longitudinal cohort study aimed to analyze the change in the annual incidence rate of central precocious puberty (CPP) among Korean children over the most recent decade, using the national registry data.

METHOD

The International Statistical Classification of Diseases and Related Health Problems, Tenth Revision (ICD-10) and insurance claims for gonadotropin-releasing hormone agonist (GnRHa) treatment were used to identify CPP patients who were using the Korean Health Insurance Review & Assessment Service (HIRA) database between 2008 and 2020. Patients who began GnRHa therapy before the age of 9 and 10 for girls and boys, respectively, were included in the study.

RESULTS

A total of 6,906 boys and 126,377 girls were diagnosed with CPP between 2008 and 2020. The annual incidence of CPP increased by 83.3 times in boys (from 1.2 to 100 per 100,000 persons) and by 15.9 times in girls (from 88.9 to 1414.7 per 100,000 persons). The age-specific annual incidence of CPP increased remarkably more in older children than in younger ones; the 2020 CPP incidence among 9-year-old boys and 8-year-old girls reached 705.2 and 7,967.3 per 100,000 persons, respectively. The annual prevalence of CPP in boys and girls increased from 2.7 to 206.5 (76.5 times) and from 141.8 to 3439.9 (24.3 times) per 100,000 persons, respectively.

CONCLUSION

Based on GnRHa treatment insurance claims, our study suggests that the annual incidence of CPP has substantially increased in Korea during the past 13 years. These findings highlight the importance of meticulous judgment by doctors in determining GnRHa treatment.

Clinical, Endocrine and Neuroimaging Findings in Girls With Central Precocious Puberty

CONTEXT

The etiology of central precocious puberty (CPP) includes a spectrum of conditions. Girls younger than age 6 years with CPP should undergo cranial magnetic resonance imaging (MRI), but it remains controversial whether all girls who develop CPP between the ages of 6 and 8 years require neuroimaging examination.

OBJECTIVE

To investigate the frequency of brain MRI abnormalities in girls diagnosed with CPP and the relationship between maternal factors, their age at presentation, clinical signs and symptoms, hormonal profiles, and neuroimaging findings.

METHODS

Data were collected between January 2005 and September 2019 from 112 girls who showed clinical pubertal progression before 8 years of age who underwent brain MRI.

RESULTS

MRI was normal in 47 (42%) idiopathic (I) scans, 54 (48%) patients had hypothalamic-pituitary anomalies (HPA) and/or extra-HP anomalies (EHPA), and 11 (10%) had brain tumors or tumor-like conditions (BT/TL), including 3 with neurological signs. Associated preexisting disorders were documented in 16. Girls with BT/TL had a higher LH peak after GnRH test (P = 0.01) than I, and those older than age 6 years had a higher craniocaudal diameter of the pituitary gland (P = 0.01); their baseline FSH and LH (P = 0.004) and peak FSH (P = 0.01) and LH (P = 0.05) values were higher than I. Logistic regression showed maternal age at menarche (P = 0.02) and peak FSH (P = 0.02) as BT/TL risk factors.

CONCLUSIONS

MRI provides valuable information in girls with CPP by demonstrating that fewer than half have a normal brain MRI and that few can have significant intracranial lesions after the age of 6, despite the absence of suggestive neurological signs.

Evaluation of Hormonal Profile and Ovarian Morphology among Adolescent Girls with Menstrual Irregularities in a Tertiary Care Centre at Central India

Menstrual disturbances are common among adolescents with a prevalence rate of 11.3–26.7%. The most frequent menstrual irregularities are oligomenorrhea, menorrhagia, polymenorrhoea, and hypomenorrhea. PCOS (polycystic ovarian syndrome) is now recognized as the most prevalent endocrine disorder among the women of reproductive age. The current study was planned to evaluate socio-demographic factors, endocrine profiles, and ovarian morphology among adolescent girls with menstrual irregularities and compare these parameters in different phenotypes of adolescent PCOS cases. It is a hospital-based cross-sectional study among 248 adolescent girls (10–19 years) with menstrual irregularities. After obtaining informed consent, history and clinical examination findings were recorded on preform proforma. All girls were assessed on day 2/3 of the menstrual cycle for hormonal profile (serum TSH, FSH, LH, prolactin, and serum testosterone) and ovarian morphology (by transabdominal ultrasonography). All participating girls were divided into three groups (groups 1, 2, and 3) corresponding to phenotypes A, B, & D as per the Rotterdam criteria. In the study, oligomenorrhea was the most common menstrual disorder (70.97%). Biochemical hyperandrogenism and thyroid dysfunction were reported in 14.91% and 8.46% of girls, respectively. Our study noted that phenotype D ,i.e., group 3 (MI + PCOM-HA; 49.43%) was the most common phenotype in the study. In a comparative analysis of different groups, significant differences (p < 0.05) in hormonal and metabolic parameters showed highest in group 2, which represents phenotype B of PCOS (hyperandrogenic anovulation). This analysis revealed that adolescent hyperandrogenism (phenotypes A and B) is associated with a more deranged hormonal and metabolic profile than nonandrogenic PCOS (phenotype D). To prevent long-term sequelae, lifestyle changes, early treatment, and close follow-up are recommended in this subset of girls.

Analysis of the Timing of Puberty in a Recent Cohort of Italian Girls: Evidence for Earlier Onset Compared to Previous Studies

BACKGROUND

Throughout the 20 century, in developed countries there has been a secular trend toward earlier menarche. Over the past 2 decades, however, there has been an apparent stabilization in the average age of menarche age in most Western countries.

OBJECTIVES

The objective of this study was to analyze the mean age of menarche in a cohort of Italian girls, to analyze the mean age of breast button appearance (B2), and to correlate the B2 developmental stage and age at menarche with the most important clinical and auxological parameters.

MATERIALS AND METHODS

We retrospectively evaluated the data of 1458 Italian girls born between 1995 and 2003. We collected the main auxological and clinical parameters, including age at B2, age at menarche, height, weight, and body mass index (BMI) at B2 and menarche and, when possible, adult/near adult height.

RESULTS

The mean age of B2 was 10.16 ± 1.00 years, significantly earlier than previously reported for Italian girls (P < .05); the mean age of menarche was 12.07 ± 0.99 years, also significantly earlier than previously reported (P < .0001). Age at B2 and menarche inversely correlated with BMI standard deviation score (SDS) (P < .0001). The mean adult/near adult height of the girls in the study cohort was not statistically different from previously reported data for Italian women.

CONCLUSIONS

Our results suggest a new trend for an earlier appearance of thelarche and menarche in Italian girls. Our data confirm a significant relationship between BMI and age of B2 and menarche. The girls' final height seems to be in line with average height for the Italian female population.

Family environmental antecedents of pubertal timing in girls and boys: A review and open questions

Across nonhuman species, pubertal timing is affected by the social environment, with consequences for reproductive success and behavior. In human beings, variations in pubertal timing have not been systematically examined in relation to social environmental antecedents, although their psychological consequences are well documented. This paper focuses on links in human beings between pubertal timing and the childhood social environment, with several sections: A review of studies relating pubertal timing to the family context, a key aspect of the social environment; challenges in studying the issue; and opportunities for future work that takes advantage of and creates links with evidence in other species. The review shows that pubertal timing in girls is accelerated by adversity in aspects of the early family social context, with effects small in size; data in boys are not sufficient to enable conclusions. Inferences from existing studies are limited by variations in conceptualizations and measurement of relevant aspects of puberty and of the family social environment, and by methodological issues (e.g., reliance on existing data, use of retrospective reports, nonrandom missing data). Open questions remain about the nature, mechanisms, and specificity of the links between early family social environment and pubertal timing (e.g., form of associations, consideration of absence of positive experiences, role of timing of exposure). Animal studies provide a useful guide for addressing these questions, by delineating potential hormonal mechanisms that underlie links among social context, pubertal timing, and behavior, and encouraging attention to aspects of the social environment outside the family, especially peers.

sCD14 Level in Saliva of Children and Adolescents with and without Dental Caries, a Hurdle Model

Objective: Soluble CD14 (sCD14) plays an important role in the innate immune response of the oral cavity. The investigation of this biomarker for detection of carious lesions is an even more actual procedure due to its non-invasiveness and the ease of withdrawal. The purpose of the present observational case-control study was to evaluate whether the quantification of sCD14 in children and adolescent’s saliva can discriminate healthy subjects from those suffering from tooth decay. Materials and Methods: 164 subjects (6 to 17 years) were selected and divided into 2 groups: those with at least 1 decayed tooth were assigned to group Decayed (n = 82) and those free from dental caries to group Healthy (n = 82). The amount of salivary soluble CD14 was quantified. Results: Mean salivary soluble CD14 was 28.3 ± 10.8 μg/mL in the Healthy group and 22 ± 9.6 μg/mL in the Decayed group. A hurdle model was applied to the data to estimate both the probability of having carious lesions and their number in relation to sCD14 levels. sCD14 was strongly associated (p < 0.01) with an inverse relation to both the probability of having caries and their number (falling rate of 5% per unit CD14 μg/mL). Conclusions: This data confirms the relationship between sCD14 and the presence of dental caries. However, there is no clear cut off level between healthy and unhealthy subjects, so it is currently not possible to use sCD14 as a biomarker to determine the risk of decays.

Gynecological and psycho-sexual aspects of women with history of anorectal malformations

PURPOSE

Women with anorectal malformation (ARM) are expected to have a normal life span, therefore, gynecological and psycho-sexual issues are also important. Aim of the study was to assess these aspects in adult females with history of ARM.

METHODS

Thirty-seven women from two ARM referral centers, aged ≥ 16, were identified. Gynecologic visit, cervicovaginal swab, pelvic ultrasound, FSH, LH, prolactin, progesterone, 17-β-estradiol, DHEAS, testosterone, TSH during follicular and luteal phases, and administration of FSFI questionnaire to screen the female sexual functioning were performed. Data were compared with six controls.

RESULTS

Nineteen patients, mean age 21.7 (16-45), participated to the study. Associated anomalies, mostly affecting limbs, vertebrae and genitalia, were present in 57.8% of cases. Mullerian anomalies were retrieved in 36.8%. Hormones' levels were normal. Concerning sexual functioning, four women (21%) reported dyspareunia or impossible penetration, four did not answer the FSFI questionnaire due to lack of confidence about their sexuality, and three scored lower than the cut-off value for female sexual function.

CONCLUSION

This study confirms the importance of a multidisciplinary long-term follow-up for ARM patients, including a careful study of the reproductive tract to detect and treat those conditions that could affect the fertility. Moreover, an appropriate psychological support should be provided.

Delayed age at menarche in chronic respiratory diseases

OBJECTIVE

Age at menarche (AAM) is an important indicator of physiological development in women, and delayed AAM has been associated with chronic illnesses. We investigated predictive factors at diagnosis that influence AAM in adolescents with chronic respiratory diseases.

STUDY DESIGN

AAM was assessed in 1207 northern Italian female aged 11-24 (1062 healthy, 98 with asthma and 47 with cystic fibrosis [CF]). AAM was defined by recall and status quo methods. We studied anthropometric data, metabolic status, diagnosis parameters, presence of irregular menses. Clinical data of subjects with chronic respiratory illness were compared with that of healthy adolescents.

RESULTS

Mean AAM for healthy adolescents was 12.49 ± 1.2 years. Mother's AAM was positively associated with that of their daughters (P < .001). BMI was negatively correlated with AAM (P < .001). 69% of healthy adolescents referred regular menses. AAM in the different groups was 12.79 ± 3.0 years for patients with asthma (P < .05 vs healthy) and 13.24 ± 1.44 years for adolescents with CF (P < .0001 vs healthy). In the asthmatic group, 57% of the patients referred regular menses, and no significant differences were found between AAM and control of the disease (ACT test). In the CF group, no correlation was found between the type of CFTR mutation or FEV1% and AAM. 53% of the patients with CF referred regular menses.

CONCLUSIONS

AAM in patients with CF and asthma was significantly higher than in healthy adolescents, and menses abnormalities were observed in the last two groups. Inflammation influences the reproductive function in chronic respiratory disease.

Menstrual patterns and disorders among Chinese women of reproductive age: A cross-sectional study based on mobile application data

Menstruation is an important indicator of women's health. Identification of abnormal menstrual patterns in adolescence may improve early diagnosis of potential health concerns in adulthood. This study aimed to evaluate menstrual patterns and disorders of Chinese women of reproductive age based on an APP.From December 2015 to January 2016, a cross-sectional study was conducted. We utilized a mobile application (APP) to collect information about participants' age at menarche, length of menstruation, duration of menstruation, amount of menstrual flow, regularity of menstrual cycle, prevalence of abnormal uterine bleeding and dysmenorrhoea.A total of 156,055 women (25,716 from the questionnaire survey and 130,000 from the mobile APP users) participated in the study. The average age of the subjects was 26.32 ± 6.97 years (median age, 25 years). Mean age at menarche was 13.08 ± 1.87 years; average length of menstrual cycle, 30.9 ± 4.28 days (median 30 days); and average duration of menstruation, 5.01 ± 1.13 days (median 5 days). Women with irregular menstrual cycles accounted for 36.41%. Women aged < 18 years and > 30 years were more likely to experience irregular menstrual cycles. The prevalence of secondary amenorrhoea was 4.07%. More than 20% of women reported abnormal menstrual flow. About 20.11% of women had abnormal uterine bleeding, and 77.65% had dysmenorrhoea. A hot compress was the most commonly used approach to ameliorate dysmenorrhoea. Women with low education and low income and those with high education and high income tended to have menstrual problems.A mobile APP as a survey tool has the advantages of large sample size, low cost, and high efficiency. The use of a mobile APP is an emerging approach for collecting big data in the field of health research. The results showed that the prevalence of menstrual disorders among Chinese reproductive women was high. Healthcare providers should educate girls and their caregivers about menstrual physiology, normal menstrual pattern, and reproductive health to prevent long-term diseases.

Trend of Menarcheal Age among Korean Girls

BACKGROUND

Menarcheal age has been decreasing worldwide. However, few recent studies have observed trends in menarcheal age in larger populations, and the cutoff age for early menarche remains unclear. Therefore, we aimed to analyze recent trends of menarcheal age and to determine the cutoff age of early menarche based on nationally representative data.

METHODS

We conducted a cross-sectional study of 351,006 Korean girls aged 12-18 years who were born in 1988-2003 based on the data of the 2006-2015 Korea Youth Risk Behavior Survey. We identified the distribution of age at menarche using the complex sample Cox regression model. Trends in the prevalence of early menarche were determined using the complex sample linear model.

RESULTS

Ninety-five percent of all the participants reported they had experienced menarche. The mean menarcheal age was 13.0 years (95% confidence intervals [CIs], 12.92-13.04) for girls born in 1988 and decreased to 12.6 years (95% CI, 12.54-12.61) for girls born in 2003. The cutoff age (the 3rd percentile value) for early menarche was 10.5 years during the study period. The prevalence of early menarche significantly increased from 1.8% in 2006 to 3.2% in 2015 (P-for-trend < 0.001). Downward trends of menarcheal age were noted across all body mass index groups, and this trend was most prominent in the obese group.

CONCLUSION

We reported an ongoing downward trend in menarcheal age in Korean girls born in 1988-2003, decreasing by 0.4 years over the 15 years.

Age at menarche in Seveso daughters exposed in utero to 2,3,7,8-tetrachlorodibenzo-p-dioxin

Supplemental Digital Content is available in the text.

In utero exposure to 2,3,7,8-tetrachlorodibenzo-p-dioxin (TCDD) is associated with delayed pubertal development in animal studies. No epidemiologic study has investigated this association. We examined the relationship of in utero exposure to TCDD with reported age at onset of menarche in female children born to a unique cohort of TCDD-exposed women resulting from an explosion in Seveso, Italy, on 10 July 1976.

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.

Menarche at an Earlier Age: Results from Two National Surveys of Israeli Youth, 2003 and 2016

STUDY OBJECTIVE

To assess emergent changes in the age at menarche and investigate associated factors in Israeli adolescents in 2003 and 2016.

DESIGN

Cross-sectional study.

SETTING

Two national representative school-based surveys (first and second "Mabat Youth").

PARTICIPANTS

Both surveys included female students in 7th-12th grades (ages 11-19 years). The first (N = 3328) was conducted between the years 2003 and 2004, and the second (N = 2535) from 2015 to 2016.

INTERVENTIONS

The survey questionnaire was self-administered and anthropometric measurements were performed by trained personnel.

MAIN OUTCOME MEASURES

The current age at menarche in Israeli girls was determined and independent factors (demographic, clinical, and lifestyle) examined. Changes that occurred since the past national survey more than a decade ago were documented.

RESULTS

The estimated median age at menarche declined from 13.0 (interquartile range, 12.0-14.0) years in 2003-2004 to 12.5 (interquartile range, 12.0-13.0) years in 2015-2016 (P < .0001). Jewish girls reached menarche earlier than Arab girls, but both populations experienced a similar downward trend in the past approximately 14 years. Greater body mass index, higher socioeconomic status, and immigrant status were associated with younger menarche onset (P < .001). Age at menarche remained lower in 2015-2016 vs 2003-2004, even after adjustment for these potential confounders, with a high hazard ratio (HR), which decreased as a function of survival time (t): HR_t = 15.417 × 0.813^t.

CONCLUSION

This study confirms the decline in age at menarche in Israel. Findings were associated with body mass index and population group but also indicated that other factors are likely involved.

Indicators of nutritional status and physical activity level as factors associated with the onset of menarche of ten year old girls from Zadar county, Croatia

OBJECTIVES

The aim is to determine the differences in nutritional status and level of physical activity (PA) of ten year old menstruating and non-menstruating girls.

METHODS

On the sample of 208 girls, fourth graders of elementary schools in Croatia, the indicators of nutritional status were measured: body mass index(BMI), body fat % and waist to hip ratio(WHR), while the PA was assessed using PAQ-C questionnaire. Welch´s t-test was applied to establish the differences and multivariate regression analysis was applied to establish the relationships.

RESULTS

Menstruating girls have significantly higher body mass (43.42 kg±8.31 vs. 38.64 kg±8.33), waist circumference (68.10 cm ± 9.86 vs. 62.22 cm ± 7.16), hip circumference (80.81 cm ± 7.24 vs. 76.63 cm ± 7.7), BMI (19.70 ± 3.42 vs. 17.74 ± 3.10), body fat % (28.05 ± 7.54 vs. 21.98 ± 7.67) and WHR (0.84 ± 0.06 vs. 0.81 ± 0.05) in comparison to non-menstruating girls, while non-menstruating girls have significantly higher PA level (2.93 ± 0.57 vs. 2.68 ± 0.57). The regression analysis have shown a significant relationship between body fat % and the onset of menarche (β=-0.23, SEβ=0.07, p<0.01).

CONCLUSIONS

Results show differences in the indicators of nutritional status of girls with regard to the status of maturity. Increased nutritional status and body fat % may be indicators of the accelerated developmental tempo and a determinant for the earlier onset of menarche.

Association of Early Menarche with Adolescent Health in the Setting of Rapidly Decreasing Age at Menarche

STUDY OBJECTIVE

This study aimed to investigate the association between age at menarche (AAM) and adverse health indicators in adolescent girls.

DESIGN

A retrospective cohort study.

SETTING

Population-based survey data.

PARTICIPANTS

A total of 319,437 female participants aged 12-18 years from the Korea Youth Risk Behaviour Web-based Survey.

INTERVENTIONS AND MAIN OUTCOME MEASURES

We assessed associations between AAM (categorized as ≤10, 11, and ≥12) and health indicators (poor self-rated health, high psychological stress, unhappiness, sexual initiation, and pregnancy). Covariates were individual-level (bodyweight, living with family, parent's education, household wealth, and presence of parents and siblings) and community-level factors (year of birth, single-sex education and level of school, urbanization level of school area, year of survey, and regional deprivation). Odds ratios (ORs) for each adverse health indicator were examined by each AAM group using multivariable regression analyses. For pregnancy, we calculated relative risks (RRs) using a log-binomial regression model.

RESULTS

Age at menarche was <12 in 42% of our study population. Nearly one-half of the girls born in the early 2000s went through menarche before the age of 12 years, whereas only one-third of girls born in the early 1990s went through menarche before the age of 12 years. Girls who experienced menarche at age ≤10 or age 11 years were more likely to show self-rated poor health (AAM ≤ 10: OR, 1.28; 95% confidence intervals [CI], 1.22-1.34; AAM = 11: OR, 1.16; 95% CI, 1.12-1.21), high stress (OR, 1.19; 95% CI, 1.14-1.23, and OR, 1.10; 95% CI, 1.06-1.14), and sexual initiation (OR, 2.21; 95% CI, 2.05-2.38, and OR, 1.32; 95% CI, 1.23-1.41) compared to those with AAM ≥12 years when data were adjusted for all covariates. AAM ≤10 years was associated with consistently higher odds for poor health than AAM ≥12 years. The ORs of sexual initiation increased with earlier AAM. Risk of pregnancy was similar across AAM groups when individual- and community-level covariates were controlled for.

CONCLUSION

Early menarche, defined as <12 years, can be still a useful indicator in adolescent health interventions to identify high-risk groups in the setting of declining AAM.

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.

Increased Vulnerability to Pregnancy and Sexual Violence in Adolescents with Precocious Menstruation

This cross-sectional, observational, and descriptive study was conducted to evaluate the association between age at menarche in the adolescent population and the age at sexual initiation, age at first pregnancy, and experience of sexual violence in the adolescent population visiting a primary health unit in Brazil. We recruited 201 female adolescents who visited the gynecology outpatient clinic of a Basic Health Unit in the Federal District of Brazil. These adolescents answered a questionnaire with regard to sexual and reproductive health during doctor's appointments. To calculate the association, we recorded data for age at menarche, age at first sexual intercourse, age at first pregnancy, and experience of sexual violence. Pearson and Mann–Whitney correlation coefficient statistical tests were performed to evaluate the association between these variables. Mean age at menarche was lower among adolescents who became pregnant (p = 0.0004) and those who experienced sexual violence (p = 0.0008). Further, there was a strong association between age at menarche and age at first sexual intercourse (p < 0.0001). This study also demonstrated that the earlier the age at menarche, the earlier was the age at sexual initiation and age at first unintended pregnancy and the greater was the risk of experiencing sexual violence. Early menarche may be considered a vulnerability factor during adolescence.

A Systematic Literature Review of Factors Affecting the Timing of Menarche: The Potential for Climate Change to Impact Women's Health

Menarche is the first occurrence of a woman’s menstruation, an event that symbolizes reproductive capacity and the transition from childhood into womanhood. The global average age for menarche is 12 years and this has been declining in recent years. Many factors that affect the timing menarche in girls could be affected by climate change. A systematic literature review was performed regarding the timing of menarche and four publication databases were interrogated: EMBASE, SCOPUS, PubMed, and Cochrane Reviews. Themes were identified from 112 articles and related to environmental causes of perturbations in menarche (either early or late), disease causes and consequences of perturbations, and social causes and consequences. Research from climatology was incorporated to describe how climate change events, including increased hurricanes, avalanches/mudslides/landslides, and extreme weather events could alter the age of menarche by disrupting food availability or via increased toxin/pollutant release. Overall, our review revealed that these perturbations in the timing of menarche are likely to increase the disease burden for women in four key areas: mental health, fertility-related conditions, cardiovascular disease, and bone health. In summary, the climate does have the potential to impact women’s health through perturbation in the timing of menarche and this, in turn, will affect women’s risk of disease in future.

BMI relationship to the onset of puberty: assessment of growth parameters and sexual maturity changes in Egyptian children and adolescents of both sexes

Background Puberty is the period of human growth and development. To determine the onset of puberty with regards to the effect of higher adiposity, together with growth parameters of the participants at various stages of sexual maturity for both sexes. Methods The study was conducted on 1944 children (8-16) years; 1022 girls (52.6%) and 922 boys (47.4%) were taken at random. Pubertal assessment was done using Tanner staging that assigned breast development in females and pubic and axillary hair in males and females. Testicular volume was recorded using a Prader orchidometer. Height, weight, body mass index (BMI), body mass (BM) fat, body fat percentage, through applying a body impedance analyzer, and others were recorded. Results The mean ages at the onset of puberty for females and males in our study were 10.29 ± 1.1 and 11.34 ± 1.02 years, respectively. Pubic hair (stage PH2) was attained at mean age of 10.72 ± 0.84 and 11.98 ± 1.03 years for females and males, respectively. For axillary hair (stage AH2), the mean age was 12.47 ± 0.68 years for females and 13.8 ± 0.58 years for males. The mean age at menarche was 12.41 ± 0.65 years. In concordance to BM fat and percentage, all pubertal stages started earlier in females with BMI ≥85th percentile comparable to females within average BMI. As for males, no significant relation was noted between mean pubertal ages and BMI values. Conclusions A significant association of mean ages of Tanner stages to excess weight especially in females warranted the increasing awareness about health care, nutritional aspects, and living circumstances.

Growth hormone therapy in children: predictive factors and short-term and long-term response criteria

PURPOSE

The definition of growth response in growth hormone (GH)-treated children is controversial. This study aims at: (1) evaluating short-term and long-term efficacy of GH treatment in a cohort of short children with GH deficiency (GHD); (2) assessing and compare various poor response criteria; (3) identifying predictive factors of growth response.

METHODS

Our study included 94 children, affected by isolated GHD and treated with GH until they reached final height. Criteria used for calculating the proportion of poor responders to GH for the first year were gain in height (ΔHt) SDS < 0.5 ("Bang criterion"), <0.3 or <0.4 SDS for less-severe and severe GHD, respectively ("Ranke criterion"), height velocity (HV) < mean -1 SDS ("Bakker criterion"); for adult height "Cianfarani criterion" was total ΔHt < 1 SDS.

RESULTS

After 1 year of treatment we defined "poor responders" 55.3% of patients according to Bang criterion, 40.9% according to Bakker criterion and 23.4% according to Ranke criterion. At the end of the treatment, poor responders according to Cianfarani criterion were 22.34%; almost everyone in our population (97.9%) achieved mMid-parental height (MPH). Median final Ht was -1.11 SDS. Our analysis revealed a significant negative association between ΔHt and age at diagnosis.

CONCLUSIONS

Bang criterion generated the highest number of poor responders, but had a low negative predictive value (67.5%); Ranke and Cianfarani criteria displayed similar rate of poor response. There is no reliable predictive factor of growth hormone response. However, almost all children treated reached MPH, suggesting good treatment efficacy.

Menstrual Cycle and Headache in Teenagers

OBJECTIVE

This population-based study on school-aged girls aimed to estimate the rate of peri-menstrual headache, evaluate headache pain pattern during the menstrual cycle, and verify its relationships with physical, psychosocial and life-style factors.

METHODS

The students (n = 4973) fulfilled a self-administered questionnaire on demographic and behavioral characteristics, menarche, menstrual pattern and features including headache and dysmenorrhea. The prevalence of headache and the mean pain intensity score at the three menstrual cycle phases (premenstrual, menstrual, in-between period) were estimated, both overall and by gynecological year. Furthermore, the prevalence of three different patterns of headache (peri menstrual/mid-cycle/acyclic) was evaluated, together with the mean pain intensity score.

RESULTS

The overall prevalence of headache at least once at any time during the menstrual cycle was 64.4%. At multivariable logistic analysis, gynecological age (OR 1.07; 95%CI 1.03-1.12), middle social level (1.24; 1.01-1.55, compared to high social level), physical activity (0.67; 0.51-0.89), oral contraceptive use (1.34; 1.04-1.73) and dysmenorrhea (2.30; 1.54-3.42) were significantly associated with headache. Among girls with headache, 83.4% had peri-menstrual headache (44.6% premenstrual, 38.8% menstrual), 3.5% mid-cycle headache and 13.2% acyclic headache. The gynaecological age and dysmenorrhea were significantly associated with the headache pattern (p = 0.03 and p < 0.0001, respectively).

CONCLUSIONS

This study suggests that peri-menstrual headache is highly prevalent among adolescents. In girls, the headache rate linearly raises with higher gynecological age; menses-related painful syndromes, such as headache and dysmenorrhea, are strongly interrelated. The anamnesis and monitoring of menstrual health should be mandatory when taking care of girls with headache.

Age at Menarche and Menstrual Abnormalities in Adolescence: Does it Matter? The Evidence from a Large Survey among Italian Secondary Schoolgirls

OBJECTIVE

To explore the independent role of age at menarche on menstrual abnormalities among adolescents.

METHODS

The present study was a multicenter cross-sectional study on a large sample (n = 3782) of Italian girls aged 13-21 y attending secondary school who already had menarche. Girls were asked to fill in a questionnaire on menarcheal age and menstrual features during the latest three menses. The gynecological age was computed as the difference between age at the survey and the age at menarche. Main outcome measures were: prevalence of oligomenorrhea, polymenorrhea, menstrual cycle irregularity, abnormal bleeding length and dysmenorrhea. Irregularity in the recent past and since menarche was also studied. Multiple logistic models were used to identify any independent association between each abnormal feature and age at menarche or gynecological age. Adjusted ORs and 95%CI were performed.

RESULTS

After adjusting for covariates, menarcheal age was not independently associated with polymenorrhea (OR = 0.81; 95%CI 0.63-1.04), oligomenorrhea (OR = 1.16; 95%CI 0.94-1.43), menstrual cycle irregularity (OR = 0.99; 95%CI 0.86-1.14), abnormal bleeding length (OR = 0.96; 95%CI 0.87-1.06) and dysmenorrhea (OR = 1.03; 95%CI 0.85-1.24). The multivariate analysis suggests that the higher prevalence of oligomenorrhea and menstrual cycle irregularity among the girls who were older at menarche might be purely explained by their younger gynecological age.

CONCLUSIONS

No evidence of any independent influence of age at menarche on menstrual abnormalities among young girls was shown by the investigation. The findings suggest that, after menarche, adolescent girls' menstrual health should be checked to monitor the endocrine system maturation and to early intercept latent disorders becoming symptomatic.

Having more siblings delays menarche in Indonesia

OBJECTIVES

Tanner (1968, Scientific American, 218(1), 21-27) concluded that having more siblings delayed menarche, but many subsequent studies have reported diverging results. We thus aimed to investigate whether the initial conclusion remains valid by controlling for sibship size and birth order together, analyzing a large number of observations, drawing on a nationally representative sample, adjusting for childhood socioeconomic status, and considering a developing country. We additionally aimed to assess the importance of sibling sex for age at menarche.

METHODS

We analyzed 10 212 ever-married women aged 20+ in the last wave of the Indonesian Family Life Survey. We regressed age at menarche on sibship size, birth spacing, and childhood socioeconomic status. We subsequently divided sibship size into the numbers of brothers and sisters.

RESULTS

Having more siblings was related to later menarche, and the relationship was strengthened when the birth order was controlled for. In addition, those born earlier experienced menarche later. Sibling sex was irrelevant to age at menarche, boosting the importance of sibship size itself.

CONCLUSIONS

Our results support the earlier conclusion that having more siblings delays menarche.

Declining age at menarche in Indonesia: a systematic review and meta-analysis

BACKGROUND

There has been much research on the average age at menarche onset. In higher income countries the lowering in average age at menarche is earlier than in middle-income countries and lower income countries. Indonesia as a middle-income country also has some research experience related to the average age at menarche for girls.

OBJECTIVES

This study aimed to review the lowering of the average age at menarche in Indonesia and to predict changes in average age at menarche.

METHODS

This study provides a systematic review and meta-analysis using references from Google Scholar, PubMed and Popline databases on the trend of age at menarche in Indonesia and other data sources from local and national survey reports. Metaprop command in STATA was used to do the meta-analysis of proportion of early age at menarche and time series with auto-regressive integrated moving average (ARIMA) models were used in analyzing the trend and predicting the age at menarche.

RESULTS

The results show that in Indonesia the timing of age at menarche onset has significantly lowered during the 40 years before 2010. There was meaningful decrease of age at menarche, which changed from 14.43 years [confident interval (CI) 95%: 14.42, 14.44] to 13.63 years (CI95%: 13.63, 13.64). Using the ARIMA model, mean age at menarche onset for the next year predicted that the coefficient regression would be -0.0245 (CI95%: -0.0275, -0.0215). The predicted average age at menarche shows a decrease of 0.0245 years (8-9 days) each year.

CONCLUSION

The findings indicate a significant lowering of age at menarche in Indonesian girls that has continued as a predictable trend through time until the present, paralleling recent socioeconomic changes. These predictions provide key indicators of a girl's future healthy transition from childhood into young adulthood.

Relationship between Age at Menarche and Metabolic Syndrome in Premenopausal Women: Korea National Health and Nutrition Examination Survey 2013-2014

BACKGROUND

Early menarche may be associated with increased risk of cardiovascular disease. The aim of this study was to evaluate the relationship between age at menarche and metabolic syndrome (MetS) in Korean premenopausal women.

METHODS

We used nationally representative data from the Korea National Health and Nutrition Examination Survey from 2013 to 2014, and 3,023 premenopausal women aged 20-55 years were our subjects. We defined early menarche as age at first menstrual period less than 12 years. Multivariable logistic regression analysis was used to evaluate the relationship between age at menarche and MetS after adjusting for current age, and socioeconomic, lifestyle, and reproductive variables.

RESULTS

MetS was much more common in women aged 40-55 years than in women aged 20-39 years (4.1% vs. 15.1%). Compared with women who experienced menarche at age 12-15 years, the risk of MetS in the early menarche group was not higher in either age group, after adjusting for current age, and socioeconomic, lifestyle, and reproductive variables (odds ratio [OR], 1.767; 95% confidence interval [CI], 0.718-4.351 in those aged 20-39 years; OR, 1.780; 95% CI, 0.775-4.085 in those aged 40-55 years). The risk of MetS in women with menarche at age ≥16 years was not higher than in women with menarche at age 12-15 years.

CONCLUSION

Early or late menarche was not associated with an increased risk of MetS in premenopausal Korean women. Even before menopause, current age has a major influence on the development of MetS.

Timing of pubertal growth and menarche in indigenous Qom girls of Argentina

BACKGROUND

Pubertal timing is in part mediated by environmental factors, with greater energy availability often associated with earlier or more rapid development. Many indigenous populations are undergoing socioeconomic change that may affect pubertal development and related health risks, necessitating fundamental longitudinal research on growth and development in these populations.

AIM

Growth velocity and time to menarche among peri-urban indigenous Qom (Toba) girls in Argentina are described.

SUBJECTS AND METHODS

From 2011-2015, monthly anthropometrics and menstrual status were collected from 61 Qom girls aged 7-14. Growth velocity curves were generated using the 'Super-imposition by translation and rotation' (SITAR) method. Median time to menarche was estimated by Kaplan-Meier survival analysis.

RESULTS

Mean ages at peak height, weight and BMI velocity were estimated at 10.8, 10.5 and 10.7 years and median age at menarche at 11.6 years (95% CI = 11.4-11.9). At menarche, 45% of girls were overweight or obese and only one participant was short-statured by international standards.

CONCLUSION

Qom participants in this study exhibit relatively fast pubertal development as compared to other Latin American indigenous populations studied previously by others. Genetic and environmental factors influencing body size, diet and/or activity levels should be investigated further in this population.

The Relationship Between Body Mass Index (BMI) and Menstrual Disorders at Different Ages of Menarche and Sex Hormones

OBJECTIVE

The present research aimed to study the relationship between body mass index and menstrual disorders at different ages of menarche and sex hormones.

METHODS

In this cross-sectional study, 2000 girls aged between 9 and 18 in all levels were selected through cluster sampling in Shiraz. Data were collected using demographic characteristics, menstrual disorders, body mass index and hormones' measure questionnaires. To analyze the data, we used SPSS 16 and Chi-square test.

RESULTS

A total of 1024 (51.2%) out of 2000 subjects had normal BMI and the smallest group belonged to 26 subjects (1.3%) with BMI ≤ 30. There is a significant relationship between body mass index, menstrual cycle length (p = 0.006), spotting (p = 0.005), passing clots (p = 0.001) and menstrual bleeding (p = 0.04), and this relationship is insignificant between body mass index and duration of bleeding (p = 0.95), amenorrhea (p = 0.03), dysmenorrhea (p = 0.26) and menstrual regularity (p = 0.95). Investigating the relationship between body mass index and some of sex hormones shows that there is no significant relationship among BMI and TSH (p = 0.94), FSH (p = 0.21), LH (p = 0.21), Prolactin (p = 0.97), Testosterone (p = 0.66), and DHEAS (p = 0.94).

CONCLUSIONS

A significant relationship among BMI and menstrual cycle length, spotting, passing clots and menstrual bleeding, and was insignificant with sex hormones.

Secular Trend of Age at Menarche in Chinese Adolescents Born From 1973 to 2004

OBJECTIVES

To estimate secular trend and factors influencing the age at menarche for Chinese girls born from 1973 to 2004.

METHODS

Data were collected from the China Health and Nutrition Survey, a prospective open cohort and an ongoing nationwide health and nutrition survey, consisting of 3199 apparently healthy Chinese girls aged 6 to 18 years at entry from 1991 to 2011. Average age at menarche and its 95% confidence interval were estimated by weighted means of Kaplan-Meier survival analysis. Cox proportional hazard models were applied to identify the independent predictive factors of age at menarche.

RESULTS

The age at menarche declined from 14.25 in Chinese girls born before 1976 to 12.60 in girls born after 2000, with an estimated decline of 0.51 years per decade (P < .001). The downward trend of age at menarche for rural girls was greater than for urban girls (0.62 vs 0.35 years per decade; P < .001). Girls living in urban areas, living in central areas, with high BMI, and with high-energy diets had a high risk of early menarche, whereas girls living on the east coast who had high-carbohydrate diets had a low risk of early menarche.

CONCLUSIONS

The authors of this study found a continuous downward secular trend of age at menarche for Chinese girls in both urban and rural areas born from 1973 to 2004. Among all variables, urban residency, BMI, and energy intake are negatively associated with age at menarche, whereas carbohydrate intake is positively associated with age at menarche.

Studying the relationship between a woman's reproductive lifespan and age at menarche using a Bayesian multivariate structured additive distributional regression model

Studies addressing breast cancer risk factors have been looking at trends relative to age at menarche and menopause. These studies point to a downward trend of age at menarche and an upward trend for age at menopause, meaning an increase of a woman's reproductive lifespan cycle. In addition to studying the effect of the year of birth on the expectation of age at menarche and a woman's reproductive lifespan, it is important to understand how a woman's cohort affects the correlation between these two variables. Since the behavior of age at menarche and menopause may vary with the geographic location of a woman's residence, the spatial effect of the municipality where a woman resides needs to be considered. Thus, a Bayesian multivariate structured additive distributional regression model is proposed in order to analyze how a woman's municipality and year of birth affects a woman's age of menarche, her lifespan cycle, and the correlation of the two. The data consists of 212,517 postmenopausal women, born between 1920 and 1965, who attended the breast cancer screening program in the central region of Portugal.

Is age of menarche among school girls related to academic performance?

Background There is strong evidence that the mean age of menarche has declined over the last few decades in developed and developing countries. This is of a major concern because of its enormous public health implications. This study aimed to estimate the age of menarche in Kuwait and investigate the association between menarcheal age and academic performance among high school girls in Kuwait. Methods A cross-sectional study was conducted on randomly selected female high school students from private and public high schools in all governorates in Kuwait. Data on the age of menarche were collected by self-administered questionnaire from the students, while data on academic performance were extracted from the students' academic records. Results Of the 907 students we selected, 800 (88.2%) responded. The mean age of menarche was 12.33 [95% confidence interval (CI) 12.18-12.49] years. There was no evidence for significant association between age of menarche and students' academic performance before or after adjusting for potential confounders. Conclusion The calculated age of menarche among contemporary girls in Kuwait is similar to that of the girls in industrialized countries. Early menarcheal age is unlikely to lead to adverse behavior that may affect academic performance in our setting.

The influence of age at menarche, menstrual cycle length and bleeding duration on time to pregnancy: a large prospective cohort study among rural Chinese women

OBJECTIVE

To investigate the relations among age at menarche (AAM), menstrual cycle length, menstrual bleeding duration and time to pregnancy in a large cohort of rural Chinese women.

DESIGN

A prospective cohort study.

SETTING

Local family-planning service agencies and maternal/child care service centres.

POPULATION

A total of 391 320 rural women of reproductive age who participated in the National Free Pre-pregnancy Checkups and were planning to conceive were enrolled.

METHODS

Menstrual characteristics were collected via face-to-face interviews. The Cox proportional hazards model were used to estimate the fecundability ratios (FRs) and 95% confidence intervals for each measure relative to its reference category.

MAIN OUTCOME MEASURES

Time to pregnancy.

RESULTS

Women with an AAM later than 14 years of age were less likely become pregnant compared with women with AAM at 13-14 years of age (FR 0.93, 95% CI 0.92-0.94). Those with menstrual cycle lengths >29 days were less likely to come pregnant (FR 0.91, 95% CI 0.90-0.92) compared with the reference cycle length of 27-29 days. Women with bleeding durations of <4 (FR 0.88; 95% CI 0.86-0.91) or >5 days (FR 0.91; 95% CI 0.90-0.91) showed lower FRs compared with those reporting 4-5 days of bleeding. The associations were independent of maternal age, ethnicity, education level, occupation, tobacco use, alcohol use and body mass index.

CONCLUSION

A later onset of menarche, longer menstrual cycle length, both shorter (<4 days) and longer (>5 days) bleeding duration were associated with a lower FR and longer time to pregnancy in rural Chinese women.

TWEETABLE ABSTRACT

A later menarche, longer cycle, shorter or longer bleeding duration were associated with lower fecundity.

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.

Age at menarche in Korean adolescents: trends and influencing factors

Background

An increased incidence of central precocious puberty has been recently reported in South Korea, which suggests an ongoing downward trend in pubertal development in the Korean population. We aimed to verify the trend in age at menarche in young Korean women during the last decade and associated factors.

Methods

We analyzed a population-based sample of 3409 Korean girls, aged 10–18 years, using data from the Korean National Health and Nutrition Examination Surveys (KNHANES) II (2001), III (2005), IV (2007–2009), and V (2010 and 2011). Average age at menarche was studied using the Kaplan-Meier survival method and predictors were analyzed using Cox proportional hazards model. The percentage of subjects who had experienced menarche at each age level was compared by using the Cochran-Armitage test.

Results

Overall mean age at menarche was 12.7 years. The percentage of subjects who experienced menarche before the age of 12 years was 21.4 % in 2001 but increased to 34.6 % in 2010/2011 (p < 0.01). In addition, the percentage of girls who experienced menarche before the age of 14 years increased from 76 % in 2001 to 92 % in 2010/2011 (p < 0.005). Adolescents whose mothers who had experienced early menarche (HR 1.48, 95 % CI [1.22–1.80]), and adolescents who were overweight (HR 1.24, 95 % CI [1.04–1.49]) were more likely to have experienced menarche. Additionally, underweight adolescents (HR 0.27, 95 % CI [0.12–0.60]) and adolescents who had a mother having late menarche (HR 0.68, 95 % CI [0.59–0.79]) were expected to have late menarche. None of the socioeconomic factors assessed in our study showed an association with age at menarche.

Conclusions

A downward trend in age at menarche was defined in Korean adolescents during the last decade. Furthermore, influences of genetic and nutritional parameters on individual variance in age at menarche were defined.

Age at Menarche and Factors that Influence It: A Study among Female University Students in Tamale, Northern Ghana

Introduction

Age at menarche reflects the health status of a population. This marks the beginning of sexual maturation and is affected by nutritional status and prevailing environmental conditions. This study measured the menarcheal age of female undergraduate students in northern Ghana and explored factors that could impact on the onset of menarche.

Method

GraphPad 5.01 was used to analyze data collected from 293 randomly selected female university students in a cross-sectional study using a semi-structured questionnaire. Association between different variables was tested using appropriate statistical tests.

Results

The mean recall age at menarche of participants in this study was 13.66 ±1.87 years for a female population of mean age, 23.04±5.07 years. Compared to female students who lived in rural settings, urban and suburban areas dwellers significantly recorded earlier menarche (p = 0.0006). Again, females from high income earning families experienced menarche earlier than those who were born to or lived with lower income earners (p = 0.003). Lower menarcheal age increased risk of experiencing menstrual pain prior to menses rather than during menstrual flow for dysmenorrhic females. (13.52±2.052 vrs 13.63±1.582 year; χ² = 7.181, df = 2, p = 0.028).

Conclusion

Mean menarcheal age of female university students in northern Ghana was 13.66 years. Females from urban areas and high income families had earlier menarche. Compared to the very first Ghanaian study reported in 1989, the menarcheal age decline was 0.11 year per decade.

Nature and Prevalence of Menstrual Disorders among Teenage Female Students at Zagazig University, Zagazig, Egypt

STUDY OBJECTIVE

To determine the nature and prevalence of menstrual disorders among teenage girls.

DESIGN

An observational descriptive cross-sectional study.

SETTING

Zagazig University Students' Hospital, Zagazig, Egypt.

PARTICIPANTS

A representative sample of female students who attended the university pre-enrollment medical examination.

INTERVENTIONS

Self-administered questionnaire covering items on the adolescents' demographic data and menstruation characteristics.

MAIN OUTCOME MEASURES

Information about menarche, body mass index, physical exercise, cycle length and regularity, duration of menses, menstrual blood loss, dysmenorrhea, and premenstrual syndrome.

RESULTS

A total of 285 questionnaires were analyzed. Mean age at menarche was 12.3 ± 1.5 years. Oligomenorrhea was reported by 18 participants (6.3%) and 5 others (1.8%) mentioned having polymenorrhea. Hypomenorrhea was noted in 25 students (8.8%), and hypermenorrhea was reported by 12 (4.2%). Irregular periods were mentioned by 24 students (8.4%). Dysmenorrhea was reported in 188 students (66.0%). Of these, 81 (28.4%) graded their pain as mild, 69 (24.2%) as moderate, and 38 (13.3%) as severe. Premenstrual syndrome was mentioned by 160 girls (56.1%). Consulting somebody regarding their menstrual problems was reported by 36 students (12.6%).

CONCLUSION

Our results are not greatly different from those in other parts of the world. Data on nature and prevalence of menstrual disorders and their effect on young women's health status, quality of life, and social integration suggest that management of these disorders should be given more attention within the available reproductive health care programs. Further research into prevalence of and risk factors for menstrual disorders and their morbidity is warranted and anxiously awaited.

Early menarche is associated with metabolic syndrome and insulin resistance in premenopausal Korean women

In pediatrics, identifying risk factors is important in planning the prevention of cardiovascular disease. The aim of this study was to determine whether there is an independent association between early menarche (<12 years) and metabolic syndrome (MetS) in Korean women. We analyzed data from 4463 premenopausal women from the Fourth Korea National Health and Nutrition Examination Survey-IV (2007-2009). MetS was defined by the International Diabetes Federation for Asians and insulin resistance (IR) was defined as HOMA-IR more than 3.05. The prevalence of MetS and IR was 7.9 and 15.0%. Women (55.6%) with MetS also showed IR. The prevalence of MetS was higher in both women with early menarche and late menarche (≥16 years) compared with the reference group (early, 12.8%; reference, 7.0%; late, 11.0%, both P = 0.002). However, the odds ratio for MetS was 3.54 (95% confidence interval (CI), 2.14-5.87) and for IR was 2.98 (95% CI, 1.99-4.47) after adjusting for age and other confounders such as lifestyle variables, reproductive variables and sociodemographic variables only in women with early menarche

CONCLUSION

Early menarche was associated with an increased risk of MetS and IR in premenopausal Korean women.

WHAT IS KNOWN

Early menarche is associated with higher risk of CVD-related death and all-cause mortality in Western studies. Early menarche is associated with higher risk of diabetes in Korean premenopausal women.

WHAT IS NEW

Early menarche (<12 years) is associated with metabolic syndrome and insulin resistance in nationally representative Korean premenopausal women. However, late menarche (>16 years) is not associated with metabolic syndrome after controlling for age and other confounders.

Decline in menarcheal age among Saudi girls

Objectives:

To estimate age at menarche and to assess trends in menarcheal age among Saudi women.

Methods:

A prospective longitudinal study was conducted among healthy prepubertal female school children and adolescents from September 2006 to July 2012 in Riyadh, Kingdom of Saudi Arabia. Study participants were invited from diverse socioeconomic backgrounds. Tanner stage, height, weight, body mass index, and socioeconomic parameters including parent’s level of education were collected. Age at menarche was compared with maternal age at menarche.

Results:

The study included 265 girls and mothers. Mean±standard deviation (SD) age at menarche for girls was 13.08 ± 1.1 years, and their distribution category across the ≤10 years was 4 (1.5%), 11-14 years was 239 (90.2%), and ≥15 years was 22 (8.3%) girls. Anthropometric measurements, mother’s level of education, and family income were not statistically significant determining factors associated with age at menarche. Mean ± SD age at menarche for mothers was 13.67 ± 1.4 years, and their distribution category across the ≤10 years was 7 (2.6%), 11-14 years was 172 (64.9%), and ≥15 years was 86 (32.5%). Girls attained menarche at younger age compared with their mothers (p<0.0001). A downward secular trend in age of menarche was observed (Cuzick test for trend = 0.049).

Conclusion:

Saudi girls attain menarcheal age earlier than their mothers, reflecting a downward secular trend in menarcheal age.

Biosocial correlates of age at menarche in a British cohort

BACKGROUND

A large number of biosocial variables have been shown to associate with age at menarche, but the results are inconsistent and differentiate not only between countries but within countries as well.

AIM

This study examined age at menarche in a British national cohort in relation to 21 biosocial and anthropometric variables.

SUBJECTS AND METHODS

The analyses were based on 4483 girls from the British National Child Development Study (NCDS).

RESULTS

The majority of girls reached menarche between 12-14 years of age. Girls from smaller families, those living in the East and South East, South West, West Midlands and Wales regions, in tied housing and uncrowded conditions, not sharing a bedroom, not having free school meals, whose families lived in households without financial problems had started menstruating earlier than their peers from families with lower socioeconomic status. However, when all the significant variables were analysed together significant associations remained only for mother's age at menarche, height and weight at 7 years, family size and tenure.

CONCLUSIONS

The results of this study support the hypotheses that intra-uterine growth and conditions in early life as well as socio-economic background are associated with the timing of menarche and that greater childhood growth and better SES are related to earlier menarche.

Childhood Passive Smoking Exposure and Age at Menarche in Chinese Women Who Had Never Smoked: The Guangzhou Biobank Cohort Study

OBJECTIVE

We examined the associations between childhood passive smoking exposure and age at menarche in women who had never smoked in southern China.

METHODS

Among 30,518 participants in Guangzhou Biobank Cohort Study (GBCS) from 2003-2008, 20,061 women who had never smoked and had complete outcome data were included. Childhood passive smoking exposure was defined as living with 1 or more smokers in the same household during childhood. Data on the number of smokers in the household and frequency of exposure (density and frequency) were also obtained. Age at menarche was measured as a continuous variable.

RESULTS

11,379 (56.7%) participants were exposed to passive smoking during childhood. Compared to those with no passive smoking exposure during childhood, those with exposure ≥ 5 days/week had menarche 0.19 year (95% confidence interval (CI): 0.13-0.25) earlier on average. Those exposed to more than two smokers had menarche 0.38 year earlier (95% CI: 0.29-0.47). Childhood exposure was associated with early age at menarche (≤ 13 vs. >13 years), with an adjusted odds ratio of 1.34 (95% CI: 1.21-1.48) for high density, and 1.17 (95% CI: 1.09-1.26) for high frequency of exposure.

CONCLUSION

Childhood passive smoking exposure was associated with earlier age at menarche, with a dose-response relationship in Chinese women who had never smoked. If causal, the results support the promotion of smoking cessation in families with children, particularly young girls.