Age at menarche and age at natural menopause in East Asian women: a genome-wide association study

Genetic contribution of reproductive traits to risk of uterine leiomyomata: a large-scale, genome-wide, cross-trait analysis

BACKGROUND

Although phenotypic associations between female reproductive characteristics and uterine leiomyomata have long been observed in epidemiologic investigations, the shared genetic architecture underlying these complex phenotypes remains unclear.

OBJECTIVE

We aimed to investigate the shared genetic basis, pleiotropic effects, and potential causal relationships underlying reproductive traits (age at menarche, age at natural menopause, and age at first birth) and uterine leiomyomata.

STUDY DESIGN

With the use of large-scale, genome-wide association studies conducted among women of European ancestry for age at menarche (n=329,345), age at natural menopause (n=201,323), age at first birth (n=418,758), and uterine leiomyomata (ncases/ncontrols=35,474/267,505), we performed a comprehensive, genome-wide, cross-trait analysis to examine systematically the common genetic influences between reproductive traits and uterine leiomyomata.

RESULTS

Significant global genetic correlations were identified between uterine leiomyomata and age at menarche (rg, -0.17; P=3.65×10-10), age at natural menopause (rg, 0.23; P=3.26×10-07), and age at first birth (rg, -0.16; P=1.96×10-06). Thirteen genomic regions were further revealed as contributing significant local correlations (P<.05/2353) to age at natural menopause and uterine leiomyomata. A cross-trait meta-analysis identified 23 shared loci, 3 of which were novel. A transcriptome-wide association study found 15 shared genes that target tissues of the digestive, exo- or endocrine, nervous, and cardiovascular systems. Mendelian randomization suggested causal relationships between a genetically predicted older age at menarche (odds ratio, 0.88; 95% confidence interval, 0.85-0.92; P=1.50×10-10) or older age at first birth (odds ratio, 0.95; 95% confidence interval, 0.90-0.99; P=.02) and a reduced risk for uterine leiomyomata and between a genetically predicted older age at natural menopause and an increased risk for uterine leiomyomata (odds ratio, 1.08; 95% confidence interval, 1.06-1.09; P=2.30×10-27). No causal association in the reverse direction was found.

CONCLUSION

Our work highlights that there are substantial shared genetic influences and putative causal links that underlie reproductive traits and uterine leiomyomata. The findings suggest that early identification of female reproductive risk factors may facilitate the initiation of strategies to modify potential uterine leiomyomata risk.

Chromosomal polymorphisms and susceptibility to menstrual disorders: a retrospective analysis of 24,578 women

PURPOSE

To evaluate the association between the polymorphic variants of chromosomes and menstrual disorders.

METHODS

The data from our previous retrospective, single-center cohort study were re-analyzed. Women with regular menstruation were included as controls. Women with menstrual cycle abnormalities were subgrouped according to reproductive causes. The frequency of chromosomal polymorphisms was compared between groups. Regression analysis was used to adjust for potential confounding variables.

RESULT

A total of 24,578 women composed of 8062 women with regular cycles as the control group and 16,516 women as the menstrual cycle irregularity group were included. When compared with the control group, the incidence of chromosomal polymorphisms in the total menstrual cycle irregularity group, Polycystic ovary syndrome group, and Primary ovarian insufficiency group were significantly higher (4.49% versus 5.34%, P = 0.004, 4.49% versus 5.35%, P = 0.018 and 4.49% versus 5.94%, P = 0.002, respectively). The incidences of inv(9) in the Primary ovarian insufficiency group were significantly higher than that in the control individuals (1.0% versus 1.6%, P = 0.024). Logistic regression analysis showed an effect of chromosomal polymorphisms on menstrual cycle irregularity (OR: 1.62, 95% CI: 1.234-2.187, P = 0.007; adjusted OR: 1.46, 95% CI: 1.153-1.819, P < 0.001). The result demonstrated an effect of chromosomal polymorphisms on the Primary ovarian insufficiency group (OR: 2.52, 95% CI: 1.307-5.177, P < 0.001; adjusted OR: 2.61, 95% CI: 1.371-4.605, P < 0.001).

CONCLUSION

The study suggests chromosomal polymorphisms adversely affect female menstrual cycle irregularity.

Age at Natural Menopause and Influencing Factors in Women Attending the Gynecological Outpatient Clinic at a Tertiary Care Hospital

Background

Menopause is the irreversible cessation of menstruation that results from the lack of ovarian follicular function and is diagnosed after 12 consecutive months of amenorrhea without reasonable cause. This study aims to determine the average age at natural menopause and identify its associated factors among Somali women.

Methods

This is a cross-sectional study conducted at the Mogadishu Somalia Türkiye Recep Tayyip Erdogan research and training hospital's Obstetrics and Gynecology outpatient clinic between June 1 and July 1, 2023. Data was collected from subjects during the data collection period using face-to-face interviews with structured questionnaires consisting of sociodemographic, lifestyle, dietary, and reproductive characteristics. A multivariate logistic regression analysis was conducted to find the association between menopause age and target variables.

Results

Out of the 188 participants recruited for the study, the median age of menopause was 45.00 (95% CI = 44.50-45.62), and 48.9% had either premature or early menopause. The majority (53.7%) of the participants had a minimum of eight children. In Spearman's rank correlation analysis, we found a significantly positive correlation between menopausal age and age at first (p<0.01), last childbirth (p<0.01), number of parities (p<0.05), and age at marriage (p<0.05). In multivariate logistic regression, we found that the odds of developing premature or early menopause among unemployed women were 59% lower than those of employed women (AOR = 0.41, 95% CI = 0.18-0.93).

Conclusion

In this study, we established that the age of natural menopause was lower than the findings reported by previous authors. We also found that employment status, education, history of contraceptive use, BMI, age at first and last childbirth, and parity were associated with age at natural menopause, suggesting that social, lifestyle, and reproductive factors may have an impact on menopausal age.

Mechanisms of ovarian aging in women: a review

Ovarian aging is a natural and physiological aging process characterized by loss of quantity and quality of oocyte or follicular pool. As it is generally accepted that women are born with a finite follicle pool that will go through constant decline without renewing, which, together with decreased oocyte quality, makes a severe situation for women who is of advanced age but desperate for a healthy baby. The aim of our review was to investigate mechanisms leading to ovarian aging by discussing both extra- and intra- ovarian factors and to identify genetic characteristics of ovarian aging. The mechanisms were identified as both extra-ovarian alternation of hypothalamic-pituitary-ovarian axis and intra-ovarian alternation of ovary itself, including telomere, mitochondria, oxidative stress, DNA damage, protein homeostasis, aneuploidy, apoptosis and autophagy. Moreover, here we reviewed related Genome-wide association studies (GWAS studies) from 2009 to 2021 and next generation sequencing (NGS) studies of primary ovarian insufficiency (POI) in order to describe genetic characteristics of ovarian aging. It is reasonable to wish more reliable anti-aging interventions for ovarian aging as the exploration of mechanisms and genetics being progressing.

Progress in genome-wide association studies of age at natural menopause

Menopause is not only the end of reproductive life, it is also related to diseases such as hyperlipidaemia, atherosclerotic cardiovascular disease, osteoporosis and breast cancer. Traditional epidemiological studies have found that heredity is the main determinant of age at natural menopause (ANM). Early studies on genetic factors were limited to candidate gene studies. Menopause age is not inherited by a single gene, but is the result of multiple gene effects. With the development of genomic technology, the Reproductive Genetics Consortium conducted several genome-wide association studies on ANM in people of European descent, and found that defects in DNA damage repair pathways were the main genetic mechanism. In recent years, due to the ethnic heterogeneity of ANM, there has been further development of global studies into multi-ethnic and trans-ethnic genome-wide association studies. Further genetic and epidemiological studies, including polygenetic score and genetic mechanism research, should be conducted to investigate the pathogenesis and mechanism with respect to menopause and its related diseases.

Next-generation sequencing of 500 POI patients identified novel responsible monogenic and oligogenic variants

BACKGROUND

Premature ovarian insufficiency refers to the loss of ovarian function before 40 years of age. The etiology is heterogeneous, and genetic factors account for 20-25% of cases. However, how to transform genetic findings to clinical molecular diagnose remains a challenge. To identify potential causative variations for POI, a next generation sequencing panel with 28 known causative genes of POI was designed, and a large cohort of 500 Chinese Han patients was screened directly. Pathogenic evaluation of the identified variants and the phenotype analysis were performed according to monogenic or oligogenic variants.

RESULTS

A total of 14.4% (72/500) of the patients carried 61 pathogenic or likely pathogenic variants in 19 of the genes in the panel. Interestingly, 58 variants (95.1%, 58/61) were firstly identified in patients with POI. FOXL2 harbored the highest occurrence frequency (3.2%, 16/500), among whom presented with isolated ovarian insufficiency instead of blepharophimosis-ptosis-epicanthus inversus syndrome. Moreover, luciferase reporter assay confirmed variant p.R349G, which account for 2.6% of POI cases, impaired the transcriptional repressive effect of FOXL2 on CYP17A1. The novel compound heterozygous variants in NOBOX and MSH4 were confirmed by pedigree haplotype analysis, and digenic heterozygous variants in MSH4 and MSH5 were firstly identified. Furthermore, nine patients (1.8%, 9/500) with digenic or multigenic pathogenic variants presented with delayed menarche, early onset of POI and high prevalence of primary amenorrhea compared with those with monogenic variation(s).

CONCLUSIONS

The genetic architecture of POI has been enriched through the targeted gene panel in a large cohort of patients with POI. Specific variants in pleiotropic genes may result in isolated POI rather than syndromic POI, whereas oligogenic defects might have cumulative deleterious effects on the severity of POI phenotype.

Genome-wide association study of age at menarche in the Taiwan Biobank suggests NOL4 as a novel associated gene

Sexual maturation is a complex physiological process that involves multiple variables, such as genetic and environmental factors. Among females, age at menarche (AM) is a critical milestone for sexual maturation. This study aimed to identify genetic markers of AM using nationwide population cohort data in Taiwan. Females with self-reported AM between 10 and 16 years (N = 39,827) were eligible for the final analysis. To identify genetic signals related to AM, we conducted a genome-wide association study using a linear regression model and split-half meta-analysis method to verify our findings. The Functional Mapping and Annotation web-based platform was used for positional mapping and gene-based and gene-set analyses. The meta-analysis identified four significant loci, i.e., LIN28B (pooled P = 1.39 × 10^-21), NOL4 (pooled P = 8.94 × 10^-9), GPR45 (pooled P = 4.19 × 10^-11), and LOC105373831 (pooled P = 4.37 × 10^-8), that were associated with AM. MAGMA gene-based analysis revealed that LIN28B (P = 1.13 × 10^-8), NOL4 (P = 2.27 × 10^-7), RXRG (P = 4.34 × 10-⁷), ETV5 (P = 1.75 × 10^-6), and HACE1 (P = 1.82 × 10^-6) were significantly associated with AM, while the gene-set analysis identified a significantly enriched pathway involving mTOR signaling complex (FDR corrected P = 1.28 × 10^-2). The results replicated evidence for several genetic markers associated with AM in the Taiwanese female population. Our analysis identified a novel locus (rs7239368) in NOL4 associated with AM (β = 0.051 ± 0.009 years, pooled P = 8.94 × 10^-9), whereas additional research is needed to validate its molecular role in sexual maturation.

Association between skull bone mineral density and periodontitis: Using the National Health and Nutrition Examination Survey (2011-2014)

BACKGROUND AND OBJECTIVE

Bone mineral density (BMD) and periodontitis have been the subject of many studies. However, the relationship between skull (including mandible) BMD and periodontitis has not been extensively studied. An objective of this cross-sectional study was to examine the relationship between skull BMD and periodontitis using data from the National Health and Nutrition Examination Surveys (NHANES) for 2011-2012 and 2013-2014.

MATERIALS AND METHODS

From NHANES 2011-2014, 3802 participants aged 30-59 were selected. We divided the skull BMD level into quartiles to check the distribution of variables. Periodontitis was defined by the Centers for Disease Control and Prevention (CDC) and the American Association of Periodontology (AAP) in 2012. Multivariate logical regression analysis was used to explore the independent relationship between skull BMD and periodontitis. The generalized additive model (GAM), smooth curve fitting (penalty spline) and threshold effect analysis was used to evaluate dose-response relationship between skull BMD and periodontitis and the potential nonlinear relationship between skull BMD and periodontitis. Finally, subgroup analysis and interaction test were conducted to determine the role of covariates between skull BMD and periodontitis.

RESULTS

The overall average skull BMD of 3802 participants was 2.24g/cm2, the average age was 43.94 years, and the prevalence of periodontitis was 41.03%. In the fully adjusted logistic regression model, skull BMD and periodontitis showed an independent negative correlation (OR 0.73, 95% CI 0.59-0.90, P = 0.0032) and a linear relationship. Compared with the lowest quartile array (Q1:1.22-1.98) of skull BMD, the highest quartile array(Q4: 2.47-3.79) had a significantly lower risk of periodontitis (OR 0.70,95% CI 0.56-0.87, P = 0.0014). Subgroup analysis showed a highly consistent negative correlation between skull BMD and periodontitis. In the interaction test, people with moderate poverty income ratio (1.57-3.62) and those who had more than 12 alcohol drinks in the past year had a lower risk of periodontitis.

CONCLUSIONS

This result suggested that periodontal disease can be related to low skull BMD, for those people, oral hygiene and health care should be more closely monitored. Validation of our findings will require further research.

Effects of age and sex on vasomotor activity and baroreflex sensitivity during the sleep-wake cycle

Cardiovascular function is related to age, sex, and state of consciousness. We hypothesized that cardiovagal baroreflex sensitivity (BRS) demonstrates different patterns in both sexes before and after 50 years of age and that these patterns are associated with patterned changes during the sleep-wake cycle. We recruited 67 healthy participants (aged 20-79 years; 41 women) and divided them into four age groups: 20-29, 30-49, 50-69, and 70-79 years. All the participants underwent polysomnography and blood pressure measurements. For each participant, we used the average of the arterial pressure variability, heart rate variability (HRV), and BRS parameters during the sleep-wake stages. BRS and HRV parameters were significantly negatively correlated with age. The BRS indexes were significantly lower in the participants aged ≥ 50 years than in those aged < 50 years, and these age-related declines were more apparent during non-rapid eye movement sleep than during wakefulness. Only BRS demonstrated a significantly negative correlation with age in participants ≥ 50 years old. Women exhibited a stronger association than men between BRS and age and an earlier decline in BRS. Changes in BRS varied with age, sex, and consciousness state, each demonstrating a specific pattern. The age of 50 years appeared to be a crucial turning point for sexual dimorphism in BRS. Baroreflex modulation of the cardiovascular system during sleep sensitively delineated the age- and sex-dependent BRS patterns, highlighting the clinical importance of our results. Our findings may aid in screening for neurocardiac abnormalities in apparently healthy individuals.

Association of life-course reproductive duration with mortality: a population-based twin cohort study

BACKGROUND

Although age at menopause has been linked to mortality, the association between the entire reproductive lifespan and mortality remains unclear.

OBJECTIVE

This study aimed to examine to what extent life-course reproductive duration is associated with all-cause mortality and explore the role of a healthy lifestyle and familial background in such an association.

STUDY DESIGN

A total of 11,669 women (mean age, 63.54 years) from the Swedish Twin Registry were followed for up to 19 years. Information on reproductive duration (the interval between ages at menarche and menopause) and lifestyle factors (including smoking, alcohol consumption, and physical activity; divided into unfavorable/intermediate/favorable) was collected on the basis of a structured questionnaire. Survival status was obtained from the Sweden Cause of Death Register. The data were analyzed using generalized estimating equation models, Laplace regression, and conditional logistic regression.

RESULTS

In the generalized estimating equation model, compared with those with ≤34 reproductive years, the odds ratio (95% confidence interval) of all-cause mortality was 0.79 (0.68-0.90) for those with ≥40 reproductive years, which prolonged survival time by 0.84 (0.24-1.43) years. Women with ≥40 reproductive years plus a favorable lifestyle (odds ratio, 0.28; 95% confidence interval, 0.23-0.35) were at a lower risk of all-cause mortality than those with <40 reproductive years plus an unfavorable lifestyle. An additive interaction between ≥40 reproductive years and a favorable lifestyle on all-cause mortality was observed (attributable proportion, 0.584; 95% confidence interval, 0.016-1.151). The odds ratios in conditional logistic regression and generalized estimating equation models did not differ significantly (P=.67).

CONCLUSION

A longer reproductive lifespan is associated with reduced all-cause mortality and prolongs survival by 0.84 years. A favorable lifestyle may amplify the beneficial effect of longer reproductive lifespan on mortality. Familial background does not account for the observed association.

Age Cutoff for Early-Onset Parkinson's Disease: Recommendations from the International Parkinson and Movement Disorder Society Task Force on Early Onset Parkinson's Disease

Background

Early-onset Parkinson's disease (EOPD)/young-onset Parkinson's disease (YOPD) is defined as Parkinson's disease (PD) with an age at onset (AAO) after age 21 years but before the usual AAO for PD. Consensus is lacking, and the reported maximal age for EOPD/YOPD has varied from 40 to 60 years, leading to a lack of uniformity in published studies and difficulty in harmonization of data. EOPD and YOPD have both been used in the literature, somewhat interchangeably.

Objective

To define the nomenclature and AAO cutoff for EOPD/YOPD.

Methods

An extensive review of the literature and task force meetings were conducted. Conclusions were reached by consensus.

Results

First, the literature has seen a shift from the use of YOPD toward EOPD. This seems motivated by an attempt to avoid age-related stigmatization of patients. Second, in defining EOPD, 56% of the countries use 50 or 51 years as the cutoff age. Third, the majority of international genetic studies in PD use an age cutoff of younger than 50 years to define EOPD. Fourth, many studies suggest that changes in the estrogen level can affect the predisposition to develop PD, making the average age at menopause of 50 years an important factor to consider when defining EOPD. Fifth, considering the differential impact of the AAO of PD on professional and social life, using 50 years as the upper cutoff for the definition of EOPD seems reasonable.

Conclusions

This task force recommends the use of EOPD rather than YOPD. It defines EOPD as PD with AAO after 21 years but before 50 years.

Heritability of Age at Menarche in Nigerian Adolescent Twins

Heritability of age at menarche (AAM) in African populations remains largely unknown. A question on AAM was given to 1803 [454 monozygotic (MZ), 823 same-sex dizygotic (DZ), and 526 female members of opposite sex] adolescent twins attending public schools in Lagos State, Nigeria. The age range of the sample was 12-18 years, with a mean (SD) of 14.57 (±1.70) years. The data included 905 missing cases consisting of those who had not experienced menarche and did not recall AAM. Missing values were imputed using the Expectation-Maximization algorithm. Kaplan-Meier analysis based on the imputed data yielded 13.23 years [95% CI [13.18, 13.28] for the mean and 13.00 years [95% CI [12.96, 13.04] for the median of AAM. Twin correlation and model-fitting analyses were performed on the basis of those who reported AAM (MZ = 82 complete pairs and 38 cotwin missing cases; DZ = 157 complete pairs and 99 cotwin missing cases). Maximum likelihood MZ and DZ twin correlations for AAM were .63 (95% CI [.48, .74]) and .33 (95% CI [.19, .45]) respectively. Model-fitting analyses indicated that 58% (95% CI [46, 67]) of the variance of AAM was associated with additive genetic influences with the remaining variance, 42% (33-54) being due to nonshared environmental influences including measurement error. The heritability estimate found in this study was within the range of those found in Asian and Western twin samples.

Association between osteoporosis and periodontal disease among menopausal women: The 2013-2015 Korea National Health and Nutrition Examination Survey

BACKGROUND

This cross-sectional study aimed to investigate the association between osteoporosis and periodontal disease among Korean menopausal women, as well as the association between osteoporosis and periodontal disease according to duration after menopause.

METHODS

Of a total of 22,948 subjects who participated in the Korea National Health and Nutrition Examination Survey, from 2013 to 2015 the final study population was limited to 2,573 subjects with no missing values. The subjects were divided into two groups, normal bone mineral density (BMD) and osteoporosis, according to the T-score obtained from bone densitometry. Scores of ≥ 3 points for the community periodontal index of treatment needs were reclassified as periodontal disease. Moreover, after stratification of the variable 'duration after menopause' into 0-4, 5-9, and ≥10 years, binary logistic regression analysis was performed to investigate the association between osteoporosis and periodontal disease according to the duration after menopause.

RESULTS

There was an association between osteoporosis and periodontal disease. The osteoporosis group had an adjusted odds ratio [OR] of 1.25 (95% confidence interval [CI]: 1.00-1.56) for periodontal disease compared to the normal BMD group. Of note, the osteoporosis group in the menopausal transition stage (0-4 years after menopause) showed an adjusted OR of 2.08 (95% CI: 1.15-3.77) for developing periodontal disease.

CONCLUSIONS

Osteoporosis was associated with periodontal disease and the association was strongest among women in the menopausal transition stage, 0-4 years after menopause. Oral health promotion, including regular oral examination and oral hygiene care, is particularly useful for menopausal transition women with osteoporosis.

OUP accepted manuscript

STUDY QUESTION

What is the scope of literature regarding women’s reproductive span in terms of definitions, trends and determinants?

SUMMARY ANSWER

The scoping review found a wide variation in definitions, trends and determinants of biological, social and effective women’s reproductive span.

WHAT IS KNOWN ALREADY

A woman’s reproductive span refers to her childbearing years. Its span influences a woman’s reproductive decisions.

STUDY DESIGN, SIZE, DURATION

A systematic scoping review was conducted. We searched MEDLINE, PubMed, JSTOR, CINAHL, Web of Science and Scopus electronic databases from inception to January 2021 without imposing language or date restrictions. We searched unpublished sources including the Global Burden of Disease, Demographic and Health Surveys, and National Health and Nutrition Examination Surveys. The list of relevant references was searched by hand. Sixty-seven reports on women’s reproductive span were included in this review.

PARTICIPANTS/MATERIALS, SETTING, METHODS

This scoping systematic review followed an established framework. The reporting of this scoping review followed the reporting requirements provided in the Preferred Reporting Items for Systematic Reviews and Meta-Analyses, Extension for Scoping Reviews. Identified records were independently screened and data were extracted. We performed conceptual synthesis by grouping the studies by available concepts of reproductive span and then summarized definitions, measures used, temporal trends, determinants, and broad findings of implications on population demographics and assisted reproduction. Structured tabulation and graphical synthesis were used to show patterns in the data and convey detailed information efficiently, along with a narrative commentary.

MAIN RESULTS AND THE ROLE OF CHANCE

A total of 67 relevant reports on women’s reproductive span were published between 1980 and 2020 from 74 countries. Most reports (42/67) were cross-sectional in design. Literature on reproductive span was conceptually grouped as biological (the interval between age at menarche and age at menopause), effective (when a woman is both fertile and engaging in sexual activity) and social (period of exposure to sexual activity). We summarized the working definitions, trends and determinants of each concept. Few articles addressed implications on demographics and assisted reproduction.

LIMITATIONS, REASONS FOR CAUTION

A formal assessment of methodological quality of the included studies was not performed because the aim of this review was to provide an overview of the existing evidence base regardless of quality.

WIDER IMPLICATIONS OF THE FINDINGS

The review produced a comprehensive set of possible definitions of women’s reproductive span, trends, and potential determinants. Further advancement of these findings will involve collaboration with relevant stakeholders to rate the importance of each definition in relation to demography and fertility care, outline a set of core definitions, identify implications for policy, practice or research and define future research opportunities to explore linkages between reproductive spans, their determinants, and the need for assisted reproduction.

STUDY FUNDING/COMPETING INTEREST(S)

This work received funding from the UNDP-UNFPA-UNICEF-WHO-World Bank Special Programme of Research, Development and Research Training in Human Reproduction (HRP), a cosponsored programme executed by the World Health Organization (WHO). The authors had no competing interests.

STUDY REGISTRATION NUMBER

N/A.

Polymorphisms of the TNF, LTA, and TNFRSF1B genes are associated with onsets of menarche and menopause in US women of European ancestry

BACKGROUND

The TNF, LTA and TNFRSF1B genes have been implicated in various traits related to menarche and menopause.

AIM

To analyse the TNF, LTA and TNFRSF1B genes for their association with ages at menarche (AM) and natural menopause (ANM).

SUBJECTS AND METHODS

The study sample consisted of 314 unrelated females of European ancestry. Twenty SNPs located in and near the genes were analysed using various statistical methods. In addition, the functional significance of the loci associated with AM and ANM was analysed in silico.

RESULTS

Locus rs2229094 of the LTA gene was associated with AM according to the additive (β = -0.295, p_perm = 0.016) and recessive (β = -0.940, p_perm = 0.016) genetic models. Haplotype GG rs1148459-rs590368 of the TNFRSF1B gene was associated with AM (β = 0.307, p_perm = 0.023). Haplotype GCA rs2844484-rs2229094-rs1799964 was associated with ANM after adjustment for covariates (β = -1.020, p_perm = 0.035). All studied loci were associated with ANM after adjustment for breastfeeding (raw p < 0.05). In addition, eight of the most significant models of interlocus interactions were associated with AM and five with ANM.

CONCLUSION

The results of the present study suggest that the TNF, LTA and TNFRSF1B genes are associated with AM and ANM.

Elementary Laboratory Assays as Biomarkers of Ageing: Support for Treatment of COVID-19?

Youth, working age and the elderly: On a timeline, chronological age (CA) and biological age (BA) may dissociate; nosological entities manifest themselves at different BAs. In determining which disease corresponds to a given age decade, statistical registries of causes of death are unreliable and this does not change with SARS CoV-2 infection. Beyond adolescence, ageing metrics involve estimations of changes in fitness, including prediction models to estimate the number of remaining years left to live. A substantial disparity in biomarker levels and health status of ageing can be observed: the difference in CA and BA in the large cohorts under consideration is glaring. Here, we focus more closely on ageing and senescence metrics in order to make information available for risk analysis non the least with COVID-19, including the most recent risk factors of ABO blood type and 3p21.31 chromosome cluster impacting on C5a and SC5b-9 plasma levels. From the multitude of routine medical laboratory assays, a potentially meaningful set of assays aimed to best reflect the stage of individual senescence; hence risk factors the observational prospective SENIORLABOR study of 1,467 healthy elderly performed since 2009 and similar approaches since 1958 can be instantiated as a network to combine a set of elementary laboratory assays quantifying senescence.

Genetics of Menopause and Primary Ovarian Insufficiency: Time for a Paradigm Shift?

This review summarizes the existing information concerning the genetic background of menopause and primary ovarian insufficiency (POI). There is overwhelming evidence that majority of genes are involved in double-strand break repair, mismatch repair, and base excision repair. The remaining loci were involved in cell energy metabolism and immune response. Gradual (or in case of rapid POI) accumulation of unrepaired DNA damage causes (premature) cell death and cellular senescence. This in turn leads to exhaustion of cell renewal capacity and cellular dysfunction in affected organs and eventually to aging of the entire soma. Similar erosion of the genome occurs within the germ cell line and the ovaries. Subsequently, the systemic "survival" response intentionally suppresses the sex-steroid hormonal output, which in turn may contribute to the onset of menopause. The latter occurs in particular when age-dependent DNA damage accumulation does not cease. Both effects are expected to synergize to promote (premature) ovarian silencing and install (early) menopause. Consequently, aging of the soma seems to be a primary driver for the loss of ovarian function in women. This challenges the current dogma which implies that loss of ovarian function initiates aging of the soma. It is time for a paradigm shift!

Menopause Transition and Cardiovascular Disease Risk: Implications for Timing of Early Prevention: A Scientific Statement From the American Heart Association

Cardiovascular disease (CVD) is the leading cause of death in women, who have a notable increase in the risk for this disease after menopause and typically develop coronary heart disease several years later than men. This observation led to the hypothesis that the menopause transition (MT) contributes to the increase in coronary heart disease risk. Over the past 20 years, longitudinal studies of women traversing menopause have contributed significantly to our understanding of the relationship between the MT and CVD risk. By following women over this period, researchers have been able to disentangle chronological and ovarian aging with respect to CVD risk. These studies have documented distinct patterns of sex hormone changes, as well as adverse alterations in body composition, lipids and lipoproteins, and measures of vascular health over the MT, which can increase a woman's risk of developing CVD postmenopausally. The reported findings underline the significance of the MT as a time of accelerating CVD risk, thereby emphasizing the importance of monitoring women's health during midlife, a critical window for implementing early intervention strategies to reduce CVD risk. Notably, the 2011 American Heart Association guidelines for CVD prevention in women (the latest sex-specific guidelines to date) did not include information now available about the contribution of the MT to increased CVD in women. Therefore, there is a crucial need to discuss the contemporary literature on menopause and CVD risk with the intent of increasing awareness of the significant adverse cardiometabolic health-related changes accompanying midlife and the MT. This scientific statement provides an up-to-date synthesis of the existing data on the MT and how it relates to CVD.

Relationship between age at menarche and chromosome numerical abnormalities in chorionic villus among missed abortions: A cross-sectional study of 459 women in China

AIMS

To assess the relationship between age at menarche and the numerical abnormalities of chorionic villi chromosomes in patients with missed abortion.

METHODS

Unexplained miscarriage patients were admitted to an outpatient clinic in Tianjin Central Hospital of Gynecology Obstetrics, China. Embryonic villi tissues were collected aseptically after curettage. Chromosome analysis was performed subsequently using multiplex ligation-dependent probe amplification method.

RESULTS

Among 459 cases of missed abortion, chromosome numerical abnormalities were found in 231 cases (50.33%). Autosomal trisomy occurs most frequently, with 16-trisomy being most common. Patients (age more than 35 years old) had more frequent miscarriages compared with those who were less than 35 years old. However, there was no statistically significant difference in chromosome numerical abnormalities. In addition, compared with patients less than 30 years old, women with age ≥ 30 years old had higher abortions frequency (P = 0.002), and the proportion of chromosome numeric abnormalities increased (P = 0.000). The number of patients with abnormal chromosomes is higher among patients whose age of menarche are less than 12 years old than that of patients whose age of menarche was over 12 years old (P = 0.003).

CONCLUSION

Chromosome numerical abnormalities are important cause of missed abortion. The incidence of chromosome numeric abnormalities increases among patients ≥30 years old. Besides, age of menarche is an important risk factor for chromosome numerical abnormalities.

Menstrual dysfunction and body weight dissatisfaction among Finnish young athletes and non-athletes

To determine the prevalence of menstrual dysfunction (MD; ie, oligomenorrhea or amenorrhea) and attitudes toward body weight among athletes and non-athletes, we studied a cohort of athletes and non-athletes, in adolescence (14-16 years) and subsequently in young adulthood (18-20 years). We further studied the differences between athletes reporting MD and eumenorrheic athletes at both time periods and identified physical and behavioral characteristics that might predict MD in young adulthood. Data were collected using questionnaires, accelerometers, and a pre-participation screening. In adolescence, the athletes reported current primary amenorrhea more often than the non-athletes (4.7% vs 0%, P = .03). In young adulthood, athletes reported MD more frequently than non-athletes (38.7% vs 5.6%, P < .001). Athletes had less desire than non-athletes to lose weight at both time points, and in adolescence, athletes were more satisfied with their weight. However, about one fifth of the athletes and about 40% of the non-athletes experienced body weight dissatisfaction at both time points. In adolescence, athletes reporting MD had lower BMI than eumenorrheic athletes. In young adulthood, athletes with MD were more physically active than eumenorrheic athletes. The only longitudinal predictor of MD in young adulthood was MD in adolescence. Our findings indicate that MD is relatively frequent among young Finnish athletes. However, athletes appear to have a smaller tendency to experience body weight dissatisfaction than their non-athletic peers. MD seems to track from adolescence to adulthood, suggesting that there is a need to focus on possible causes at the earliest feasible phase of an athlete's career.

Breast cancer epidemiology among surgically treated patients in Jordan: A retrospective study

Background: Multiple risk factors contribute to the development of breast cancer, including age, positive family history, early menarche, late menopause and the strongest factor being female gender. In this study, we aimed to investigate the proportion of breast cancer patients with certain risk factors, the prevalence of each cancer type, in addition to the surgical procedures performed.

Methods: The medical records of patients diagnosed with breast cancer from January 2010 to November 2015 were evaluated retrospectively regarding demographics, breast cancer risk factors, comorbidities, diagnostic methods, tumor location, cancer type and stage, pathological findings, tumor markers, harvested lymph nodes and the types of surgical procedures. The collected data were statistically analyzed as number, mean, and frequency as percentages. Cases with deficient medical records were excluded from the analysis of certain parameters.

Results: The sample consisted of 120 patients, 118 (98.3%) of whom were women. The mean age was 56.5±12.0 years. The most common diagnostic method at presentation was self-exam in 93.3% of patients. Invasive ductal carcinoma was the most common type of tumor (80.0%). The pathological stages could be determined for only 106 patients, and 26 patients (24.5%) were at stage 1 disease, 45 patients (42.5%) were at stage 2 whereas 34 patients (32.1%) were at stage 3. According to the results of pathological examinations, 72.6% (85 patients) of the cases were estrogen receptor positive, 61.2% (71 patients) were progesterone receptor positive while 24.8% (27 patients) were HER positive. Modified radical mastectomy (MRM) was performed in 52 (43.3%) patients and wide local excision (WLE) was preferred in 46 (38.3%) cases.

Conclusion: Advanced age, positive family history, and prolonged estrogen exposure were remarkable in the majority of patients. Moreover, the most common type of breast cancer was invasive ductal carcinoma, and around half of the patients presented at stage 2 disease. Modified radical mastectomy and WLE were the most commonly performed surgical procedures.

Sex differences in postsurgical skeletal muscle depletion after donation of living-donor liver transplantation, although minimal, should not be ignored

Background

Donor safety is the top priority in living-donor liver transplantation. Splenic hypertrophy and platelet count decrease after donor surgery are reported to correlate with the extent of hepatectomy, but other aftereffects of donor surgeries are unclear. In this study, we evaluated the surgical effects of donor hepatectomy on skeletal muscle depletion and their potential sex differences.

Methods

Among a total of 450 consecutive donor hepatectomies performed from April 2001 through March 2017, 277 donors who completed both preoperative and postoperative (60–119 days postsurgery) evaluation by computed tomography were the subjects of this study. Donors aged 45 years or older were considered elderly donors. Postoperative skeletal muscle depletion was assessed on the basis of the cross-sectional area of the psoas major muscle. Postoperative changes in the spleen volume and platelet count ratios were also analysed to evaluate the effects of major hepatectomy.

Results

The decrease in the postoperative skeletal muscle mass in the overall donor population was slight (99.4 ± 6.3%). Of the 277 donors, 59 (21.3%) exhibited skeletal muscle depletion (i.e., < 95% of the preoperative value). Multivariate analysis revealed that elderly donor (OR:2.30, 95% C.I.: 1.27–4.24) and female donor (OR: 1.94, 95% C.I. 1.04–3.59) were independent risk factors for postoperative skeletal muscle depletion. Stratification of the subjects into four groups by age and sex revealed that the elderly female donor group had significantly less skeletal muscle mass postoperatively compared with the preoperative values (95.6 ± 6.8%), while the other three groups showed no significant decrease. Due to their smaller physical characteristics, right liver donation was significantly more prevalent in the female groups than in the male groups (112/144, 77.8% vs 65/133, 48.9%; p < 0.001). The estimated liver resection rate correlated significantly with the splenic hypertrophy ratio (r = 0.528, p < 0.001) and the extent of the platelet count decrease (r = − 0.314, p < 0.001), but donor age and sex did not affect these parameters.

Conclusion

Elderly female donors have a higher risk of postoperative skeletal muscle depletion. Additionally, female donors are more likely to donate a right liver graft, whose potential subclinical risks include postoperative splenic enlargement and a platelet count decrease.

Homozygous variants in SYCP2L cause premature ovarian insufficiency

Background

The genetic causes of the majority of cases of female infertility caused by premature ovarian insufficiency (POI) are unknown.

Objective

To identify the genetic causes of POI in 110 patients.

Methods

Whole-exome sequencing was performed on 110 patients with POI, and putative disease-causative variants were validated by Sanger sequencing. Bioinformatic and in vitro functional analyses were performed for functional characterisation of the identified candidate disease-causative variants.

Results

We identified two homozygous variants (NM_001040274: c.150_151del (p.Ser52Profs*7), c.999A>G (p.Ile333Met)) in SYCP2L in two patients, which had co-segregated with POI in these families. Bioinformatic analysis predicted that the two variants are deleterious, and in vitro functional analysis showed that mutant SYCP2L proteins exhibited mislocalisation and loss of function.

Conclusions

SYCP2L is a novel gene found to be responsible for human POI. Our findings provide a potential molecular marker for POI and improve the understanding of the genetic basis of female infertility.

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.

Association between serum uric acid levels and dyslipidemia in Chinese adults: A cross-sectional study and further meta-analysis

This study aimed to investigate the association of serum uric acid (SUA) levels with dyslipidemia and its components and to further explore the age- and gender-specific association of SUA levels with dyslipidemia in Chinese adults.A cross-sectional study was performed among 8642 adults who underwent health examinations. A meta-analysis covering 17 studies was conducted to confirm the results.The prevalence of hyperuricemia and dyslipidemia was 9.25% and 20.44%, respectively. Participants with hyperuricemia had higher prevalence of dyslipidemia than those without hyperuricemia (34.42% vs 19.01%, P < .005). Compared with participants with SUA in the first quintile, the odds ratio (OR) (95% confidence interval) of dyslipidemia in the second, third, fourth, and fifth quintiles of SUA were 1.095 (0.901-1.332), 1.582 (1.315-1.904), 2.095 (1.752-2.505), and 3.212 (2.702-3.818), respectively. Subgroup analysis showed that SUA quintiles were significantly correlated with the likelihood of dyslipidemia in females aged > 50 years and in males, but not in females aged ≤50 years. The meta-analysis also showed that hyperuricemia increased the likelihood of dyslipidemia and the pooled OR for the highest uric acid level vs the lowest uric acid level was 1.84 (1.49-2.28).SUA levels are significantly associated with dyslipidemia, and this association is impacted by age and gender.

Individual evaluation of luteinizing hormone in aged C57BL/6 J female mice

In female mammals, reproductive senescence is a complex process involving progressive ovarian dysfunction associated with an altered central control of the hypothalamic-pituitary axis. The objective of this study was to compare the longitudinal change in preovulatory luteinizing hormone (LH) secretion as well as estrous cycle in individual C57BL/6 J female mice at 3, 6, 9 and 12 months. Amplitude and timing of LH secretion at the surge were similar from 3 to 9 months but were altered in 12-month old mice with a significant decrease of more than 50% of peak LH value and a 2 h delay in the occurrence of the LH surge as compared to younger mice. The analysis of two to three successive LH surges at 3, 6, 9 and 12 months showed low and similar intra-individual variability at all ages. The estrous cycle length and intra/inter variability were stable over the age. This study shows that female mice in regular environmental conditions display stable LH surge timing and amplitude up to 9 months, but at 12 months, the LH surge is delayed with a reduced amplitude, however without overt modification in the estrous cycles. Analysis of individual preovulatory LH secretion and estrous cycle indicates that mice can be followed up to 9 months to investigate the detrimental effects of various parameters on mouse reproductive activity.

Effect of caloric restriction and rapamycin on ovarian aging in mice

Caloric restriction (CR) increases the preservation of the ovarian primordial follicular reserve, which can potentially delay menopause. Rapamycin also increases preservation on the ovarian reserve, with similar mechanism to CR. Therefore, the aim of our study was to evaluate the effects of rapamycin and CR on metabolism, ovarian reserve, and gene expression in mice. Thirty-six female mice were allocated into three groups: control, rapamycin-treated (4 mg/kg body weight every other day), and 30% CR. Caloric restricted females had lower body weight (P < 0.05) and increased insulin sensitivity (P = 0.003), while rapamycin injection did not change body weight (P > 0.05) and induced insulin resistance (P < 0.05). Both CR and rapamycin females displayed a higher number of primordial follicles (P = 0.02 and 0.04, respectively), fewer primary, secondary, and tertiary follicles (P < 0.05) and displayed increased ovarian Foxo3a gene expression (P < 0.05). Despite the divergent metabolic effects of the CR and rapamycin treatments, females from both groups displayed a similar increase in ovarian reserve, which was associated with higher expression of ovarian Foxo3a.

Age at natural menopause in Koreans: secular trends and influences thereon

OBJECTIVES

Age at natural menopause (ANM) has become an important health issue in older women. We explored secular trends in ANM in Korea during the past decade, and defined factors predicting ANM.

METHODS

A total of 12,761 naturally menopausal women were selected from the 2001 to 2014 data of the Korea National Health and Nutrition Examination Survey, stages II to VI. The participants were divided into four groups based on 5-year ANM categories: <45, 45 to 49, 50 to 54, and ≥55 years. To identify factors associated with ANM, the regression analysis was used.

RESULTS

Both the mean (SE) and median (SE) ANM were 49.30 (0.07) years. The cumulative proportion of women experiencing menopause before the age of 40, 45, 50, and 55 years was 3.6%, 11.8%, 46.0%, and 90.3%, respectively. The mean (SE) ANM in women born in 1929 or earlier, and between 1930 to 1934, 1935 to 1939, 1940 to 1944, and 1945 to 1949, was 47.9 (0.3), 48.1 (0.2), 48.8 (0.2), 50.1 (0.2), and 50.5 (0.1) years, respectively (P < 0.001). Residence in a rural area (odds ratio [OR] 1.82), low weight status (OR 1.61), a history of or current smoking, a low educational level, being without a partner, and participating in at least moderate physical activity (OR 1.47, 1.33, 1.32, and 1.26, respectively) were more likely to result in an early ANM. Women with prior childbirth were less likely to experience early menopause (OR 0.34). In contrast, late menopause was associated with obesity and being overweight (OR 1.63 and 1.27).

CONCLUSIONS

We found that the mean ANM exhibited upward secular trends. Socioeconomic status and lifestyle factors were the principal independent factors affecting ANM.

Heritability of Age at Menarche in South Korean Female Twins

Genetic and environmental influences on age at menarche (AAM) have rarely been examined in Asian females. This study aimed to investigate the heritability of AAM in South Korean female twins. The AAM data from 1370 female twins (933 monozygotic [MZ] twins, 294 dizygotic [DZ] twins and 160 female members of opposite-sex DZ twins) born between 1988 and 2001 were analyzed. The age of the sample at the time of the assessment ranged from 16 to 28 years with a mean of 19.3 (SD = 2.2) years. The mean AAM in the total sample was 12.49 (SD = 1.41) years. Although the mean AAM decreased with increasing birth years, it levelled off in birth years 2000-2001. Maximum likelihood MZ and DZ twin correlations were 0.72 [95% CI (0.67, 0.76)] and 0.35 [95% CI (0.19, 0.50)], respectively. The results of model-fitting analysis indicated that the additive genetic and individual-specific environmental effects were 72% [95% CI (67%, 76%)] and 28% [95% CI (24%, 33%)], respectively. Neither nonadditive genetic nor shared environmental effects were significant.

Age at menarche and epithelial ovarian cancer risk: A meta-analysis and Mendelian randomization study

Age at menarche (AAM) was found to be associated with ovarian cancer risk in previous observational studies. However, the causality of this association remains unclear. Here, after systematic meta-analyses, we performed two-sample Mendelian randomization (MR) analyses to evaluate the causal effect of AAM in epithelial ovarian cancer (EOC) etiology. We performed meta-analyses including 11 410 cases and 1 163 117 noncases to quantitatively evaluate the association between AAM and ovarian cancer risk. In MR analyses, we used 25 single nucleotide polymorphisms (SNPs) associated with AAM for Chinese and 390 SNPs for Europeans as instrumental variables. MR estimates were calculated using inverse-variance weighted methods from 1044 cases and 1172 controls in a Chinese genome-wide association study and validated by the Ovarian Cancer Association Consortium and Consortium of Investigators of Modifiers of BRCA1/2 studies with 29 396 cases and 68 502 controls of European ancestry. In meta-analyses, we observed an inverse association (odds ratio [OR] = 0.96, 95% confidence interval [CI] = 0.93 to 1.00, P = 0.036) between per year older AAM and ovarian cancer risk in case-control studies, but no association was observed in cohort studies. In MR analyses, the OR of EOC risk per year increase in AAM was 0.81 (95% CI = 0.67 to 0.97, P = 0.026) in Chinese and 0.94 (95% CI = 0.90 to 0.98, P = 0.003) in Europeans, respectively. Our study supports a causal association between AAM and EOC risk.

Age at menarche and clinical outcomes following medically assisted reproduction (MAR): a cohort study

Medically assisted reproduction (MAR) technologies have advanced rapidly, but in contrast to the specificity of modern approaches, they provide limited effectiveness in the management of the infertile couple. The purpose of this study was to assess the possible relationship between age at menarche and MAR outcomes of clinical pregnancy, live birth and the adverse incident of miscarriage, and to determine the offspring sex ratio according to age at menarche. In a cohort of 254 infertile couples who underwent 426 IVF/ICSI cycles, statistical analysis was performed by applying Student's t-test, chi-square test, and logistic regression models, adequately in the respective parameters and outcomes. The results indicated a strong association of age at menarche with the outcomes of clinical pregnancy (p = .0007) and live birth (p < .0001), especially by applying a threshold of 12 years in the first occurrence of menstruation (p = .0019 for clinical pregnancy, p < .0001 for live birth), also demonstrating a negative effect for earlier menarche that acts in parallel with the increasing age of the woman. Calculation of sex ratio demonstrated a tendency towards female offspring close to the age at menarche of 12 years. Age at menarche could serve as a surrogate parameter for reproductive potential towards personalized management of infertility.

Analysis of Antioxidant Consumption, Body Mass Index and the Waist-Hip Ratio in Early Postmenopause

Oxidative stress is present in early postmenopause. Antioxidants, present in food, avoid or limit the damage caused by free radicals. The aim of this study was to analyze whether the consumption of vitamin A, vitamin C, and Selenium was adequate in postmenopausal women and its relationship with levels of malondialdehyde. A descriptive, cross-sectional prospective clinical study was carried out with 132 women (45–55 years old) in postmenopause. The body mass index (BMI) and the waist-to-hip ratio (WHR) were calculated. The participants were surveyed about their food consumption for seven days. The plasmatic concentration of malondialdehyde was quantified by the methyl-phenyl-indole method. The women were grouped according to their BMI. All groups showed similar consumption of proteins, lipids, and carbohydrates, which exceeded the daily recommended level. According to the WHR, 87% had android fat distribution. Selenium, vitamin C, and vitamin A intake were below the daily recommended/suggested levels. The greater the BMI, the higher the plasmatic concentration of malondialdehyde in the patients. It was observed an elevated caloric intake, android fat distribution, and a greater BMI was accompanied by a lower consumption of antioxidants and an increased level of malondialdehyde.

Genetics of pubertal timing

PURPOSE OF REVIEW

To summarize advances in the genetics underlying variation in normal pubertal timing, precocious puberty, and delayed puberty, and to discuss mechanisms by which genes may regulate pubertal timing.

RECENT FINDINGS

Genome-wide association studies have identified hundreds of loci that affect pubertal timing in the general population in both sexes and across ethnic groups. Single genes have been implicated in both precocious and delayed puberty. Potential mechanisms for how these genetic loci influence pubertal timing may include effects on the development and function of the GnRH neuronal network and the responsiveness of end-organs.

SUMMARY

There has been significant progress in identifying genetic loci that affect normal pubertal timing, and the first single-gene causes of precocious and delayed puberty are being described. How these genes influence pubertal timing remains to be determined.

The genetic underpinnings of variation in ages at menarche and natural menopause among women from the multi-ethnic Population Architecture using Genomics and Epidemiology (PAGE) Study: A trans-ethnic meta-analysis

Current knowledge of the genetic architecture of key reproductive events across the female life course is largely based on association studies of European descent women. The relevance of known loci for age at menarche (AAM) and age at natural menopause (ANM) in diverse populations remains unclear. We investigated 32 AAM and 14 ANM previously-identified loci and sought to identify novel loci in a trans-ethnic array-wide study of 196,483 SNPs on the MetaboChip (Illumina, Inc.). A total of 45,364 women of diverse ancestries (African, Hispanic/Latina, Asian American and American Indian/Alaskan Native) in the Population Architecture using Genomics and Epidemiology (PAGE) Study were included in cross-sectional analyses of AAM and ANM. Within each study we conducted a linear regression of SNP associations with self-reported or medical record-derived AAM or ANM (in years), adjusting for birth year, population stratification, and center/region, as appropriate, and meta-analyzed results across studies using multiple meta-analytic techniques. For both AAM and ANM, we observed more directionally consistent associations with the previously reported risk alleles than expected by chance (p-values_binomial≤0.01). Eight densely genotyped reproductive loci generalized significantly to at least one non-European population. We identified one trans-ethnic array-wide SNP association with AAM and two significant associations with ANM, which have not been described previously. Additionally, we observed evidence of independent secondary signals at three of six AAM trans-ethnic loci. Our findings support the transferability of reproductive trait loci discovered in European women to women of other race/ethnicities and indicate the presence of additional trans-ethnic associations both at both novel and established loci. These findings suggest the benefit of including diverse populations in future studies of the genetic architecture of female growth and development.

Elucidating the genetic architecture of reproductive ageing in the Japanese population

Population studies elucidating the genetic architecture of reproductive ageing have been largely limited to European ancestries, restricting the generalizability of the findings and overlooking possible key genes poorly captured by common European genetic variation. Here, we report 26 loci (all P < 5 × 10^–8) for reproductive ageing, i.e. puberty timing or age at menopause, in a non-European population (up to 67,029 women of Japanese ancestry). Highlighted genes for menopause include GNRH1, which supports a primary, rather than passive, role for hypothalamic-pituitary GnRH signalling in the timing of menopause. For puberty timing, we demonstrate an aetiological role for receptor-like protein tyrosine phosphatases by combining evidence across population genetics and pre- and peri-pubertal changes in hypothalamic gene expression in rodent and primate models. Furthermore, our findings demonstrate widespread differences in allele frequencies and effect estimates between Japanese and European associated variants, highlighting the benefits and challenges of large-scale trans-ethnic approaches.

The timing of female reproductive capacity is influenced by genetic and environmental factors. Here, in genome-wide association studies, the authors identify genetic loci for age at menarche and onset of menopause in Japanese women, and highlight differences with European populations.

Age at menarche and cardiovascular risk factors using Mendelian randomization in the Guangzhou Biobank Cohort Study

Observational studies show earlier age at menarche associated with higher risk of cardiovascular disease although these studies could be confounded by childhood obesity or childhood socioeconomic position. We tested the hypothesis that earlier age at menarche is associated with poorer cardiovascular risk factors using a Mendelian randomization design. We conducted a Mendelian randomization study in a large Southern Chinese cohort, the Guangzhou Biobank Cohort Study (n=12,279), to clarify the causal role of menarche in cardiovascular disease risk factors including blood pressure, lipids, fasting glucose, adiposity and type 2 diabetes. A genetic allele score was obtained from single nucleotide polymorphisms associated with age at menarche using stepwise regression and with cross validation. Estimates of the association of age at menarche with cardiovascular disease risk factors were obtained using two stage least squares regression. Height was included as a positive control outcome. The F-statistic for the allele score (rs17268785, rs1859345, rs2090409, rs4452860 and rs4946651) was 19.9. Older age at menarche was associated with lower glucose (-0.39mmol/L per year older menarche, 95% confidence interval (CI) -0.78 to -0.001) but not clearly with any other cardiovascular risk factors. Older age at menarche was also associated with taller height. Age at menarche did not appear to affect cardiovascular disease risk factors except for glucose in an inverse manner. However, these results need to be confirmed in larger Mendelian randomization studies.

Association between age at menarche and cardiovascular disease: A systematic review on risk and potential mechanisms

Age at menarche (AAM) has been reported to be associated with the risk of cardiovascular disease (CVD), but the shape of and the mechanisms behind this association remain unclear. We reviewed the data on the association between AAM and different subtypes of CVD, and used shared genetic loci to identify possible mechanisms underlying this association using shared genetic association. We searched the databases of PubMed, Web of Science and Embase through to April 2017. We included articles with any clinically manifest CVD endpoint and for any ethnicity. We identified single nucleotide polymorphisms (SNPs) for AAM in genome-wide association studies (GWAS) in Caucasians through PubMed and HuGE Navigator, and searched whether these SNPs or any of their proxies were associated with any CVD-related trait. Eight studies in Caucasian populations reported an inverse linear relation between AAM and CVD risk, whereas one large study reported a significant U-shaped relation between them. Data from Asian populations were contradictory and inconclusive. In total, 122 AAM SNPs were identified at a genome-wide significance level (p<5×10^-8). Of those, 18 were also associated with various CVD-related traits, primarily body mass index (BMI), obesity, and height. In conclusion, early AAM and possibly also late AAM increase the risk of CVD in Caucasian populations. Weight and height may be part of the mechanism underlying the relation between AAM and CVD risk in Caucasians. Data on other ethnicities are too limited for meaningful analysis and conclusions.

Epidemiology of ovarian cancer: a review

Ovarian cancer (OC) is the seventh most commonly diagnosed cancer among women in the world and the tenth most common in China. Epithelial OC is the most predominant pathologic subtype, with five major histotypes that differ in origination, pathogenesis, molecular alterations, risk factors, and prognosis. Genetic susceptibility is manifested by rare inherited mutations with high to moderate penetrance. Genome-wide association studies have additionally identified 29 common susceptibility alleles for OC, including 14 subtype-specific alleles. Several reproductive and hormonal factors may lower risk, including parity, oral contraceptive use, and lactation, while others such as older age at menopause and hormone replacement therapy confer increased risks. These associations differ by histotype, especially for mucinous OC, likely reflecting differences in etiology. Endometrioid and clear cell OC share a similar, unique pattern of associations with increased risks among women with endometriosis and decreased risks associated with tubal ligation. OC risks associated with other gynecological conditions and procedures, such as hysterectomy, pelvic inflammatory disease, and polycystic ovarian syndrome, are less clear. Other possible risk factors include environmental and lifestyle factors such as asbestos and talc powder exposures, and cigarette smoking. The epidemiology provides clues on etiology, primary prevention, early detection, and possibly even therapeutic strategies.

Epidemiology of ovarian cancer: a review

Ovarian cancer (OC) is the seventh most commonly diagnosed cancer among women in the world and the tenth most common in China. Epithelial OC is the most predominant pathologic subtype, with five major histotypes that differ in origination, pathogenesis, molecular alterations, risk factors, and prognosis. Genetic susceptibility is manifested by rare inherited mutations with high to moderate penetrance. Genome-wide association studies have additionally identified 29 common susceptibility alleles for OC, including 14 subtype-specific alleles. Several reproductive and hormonal factors may lower risk, including parity, oral contraceptive use, and lactation, while others such as older age at menopause and hormone replacement therapy confer increased risks. These associations differ by histotype, especially for mucinous OC, likely reflecting differences in etiology. Endometrioid and clear cell OC share a similar, unique pattern of associations with increased risks among women with endometriosis and decreased risks associated with tubal ligation. OC risks associated with other gynecological conditions and procedures, such as hysterectomy, pelvic inflammatory disease, and polycystic ovarian syndrome, are less clear. Other possible risk factors include environmental and lifestyle factors such as asbestos and talc powder exposures, and cigarette smoking. The epidemiology provides clues on etiology, primary prevention, early detection, and possibly even therapeutic strategies.

Epidemiology of ovarian cancer: a review

Ovarian cancer (OC) is the seventh most commonly diagnosed cancer among women in the world and the tenth most common in China. Epithelial OC is the most predominant pathologic subtype, with five major histotypes that differ in origination, pathogenesis, molecular alterations, risk factors, and prognosis. Genetic susceptibility is manifested by rare inherited mutations with high to moderate penetrance. Genome-wide association studies have additionally identified 29 common susceptibility alleles for OC, including 14 subtype-specific alleles. Several reproductive and hormonal factors may lower risk, including parity, oral contraceptive use, and lactation, while others such as older age at menopause and hormone replacement therapy confer increased risks. These associations differ by histotype, especially for mucinous OC, likely reflecting differences in etiology. Endometrioid and clear cell OC share a similar, unique pattern of associations with increased risks among women with endometriosis and decreased risks associated with tubal ligation. OC risks associated with other gynecological conditions and procedures, such as hysterectomy, pelvic inflammatory disease, and polycystic ovarian syndrome, are less clear. Other possible risk factors include environmental and lifestyle factors such as asbestos and talc powder exposures, and cigarette smoking. The epidemiology provides clues on etiology, primary prevention, early detection, and possibly even therapeutic strategies.