Age at natural menopause and associated factors with early and late menopause among Chinese women in Zhejiang province: A cross-sectional study

OBJECTIVES

Menopause is a significant life transition for women, impacting their physical and psychological health. The age at natural menopause (ANM) and its associated factors have differed by race and region. This study aimed to investigate ANM and associated factors of early and late menopause among Chinese women in Zhejiang province.

METHODS

A cross-sectional study was conducted using a multi-stage stratified cluster sampling method to recruit 8,006 women aged 40-69 years who had resided in Zhejiang province for over 6 months between July 2019 and December 2021. Self-reported ANM and sociodemographics, lifestyle behaviors, reproductive history, and health-related factors were collected using questionnaires in face-to-face surveys. ANM were categorized into three groups: early menopause (<45 years), normal menopause (45-54 years), and late menopause (≥55 years). Kaplan-Meier survival analysis was utilized to calculate the median ANM. Multivariable multinomial logistic regression was employed to explore the associated factors of early menopause and late menopause.

RESULTS

A total of 6,047 women aged 40-69 years were included for survival analysis, with 3,176 of them for the regression analysis. The overall median ANM was 51 years (Inter-quartile range [IQR]: 51-52). Women who were smokers (odds ratio [OR]:4.54, 95% confidence interval [CI]:1.6-12.84), had irregular menstrual cycles (OR:1.78, 95% CI:1.12-2.83) and hypertension (OR:1.55, 95% CI:1.09-2.21) had a higher odds ratio of early menopause, while central obesity (OR:1.33, 95% CI:1.03-1.73) and hyperlipidemia (OR:1.51, 95% CI:1.04-2.18) were factors associated with late menopause.

CONCLUSIONS

This study revealed the associations between ANM and various factors among Chinese women. These factors included socio-demographic factors such as age; life behavior factors like current or prior smoking status; reproductive history factors such as irregular menstrual cycles, miscarriages, and breastfeeding; and health-related factors like central adiposity, hypertension, and hyperlipidemia. These findings provided a basis for understanding factors associated with ANM.

A systematic review and evidence assessment of monogenic gene-disease relationships in human female infertility and differences in sex development

BACKGROUND

As in other domains of medicine, high-throughput sequencing methods have led to the identification of an ever-increasing number of gene variants in the fields of both male and female infertility. The increasing number of recently identified genes allows an accurate diagnosis for previously idiopathic cases of female infertility and more appropriate patient care. However, robust evidence of the gene-disease relationships (GDR) allowing the proper translation to clinical application is still missing in many cases.

OBJECTIVE AND RATIONALE

An evidence-based curation of currently identified genes involved in female infertility and differences in sex development (DSD) would significantly improve both diagnostic performance and genetic research. We therefore performed a systematic review to summarize current knowledge and assess the available GDR.

SEARCH METHODS

PRISMA guidelines were applied to curate all available information from PubMed and Web of Science on genetics of human female infertility and DSD leading to infertility, from 1 January 1988 to 1 November 2021. The reviewed pathologies include non-syndromic as well as syndromic female infertility, and endocrine and reproductive system disorders. The evidence that an identified phenotype is caused by pathogenic variants in a specific gene was assessed according to a standardized scoring system. A final score (no evidence, limited, moderate, strong, or definitive) was assigned to every GDR.

OUTCOMES

A total of 45 271 publications were identified and screened for inclusion of which 1078 were selected for gene and variant extraction. We have identified 395 genes and validated 466 GDRs covering all reported monogenic causes of female infertility and DSD. Furthermore, we present a genetic diagnostic flowchart including 105 genes with at least moderate evidence for female infertility and suggest recommendations for future research. The study did not take into account associated genetic risk factor(s) or oligogenic/polygenic causes of female infertility.

WIDER IMPLICATIONS

We have comprehensively reviewed the existing research on the genetics of female infertility and DSD, which will enable the development of diagnostic panels using validated genes. Whole genome analysis is shifting from predominantly research to clinical application, increasing its diagnostic potential. These new diagnostic possibilities will not only decrease the number of idiopathic cases but will also render genetic counselling more effective for infertile patients and their families.

Premature menopause among women in India: Evidence from National Family Health Survey-IV

AIM

Women who experience premature menopause either due to biological or induced reasons have a longer duration of exposure to severe symptoms and adverse health consequences when compared to those who undergo menopause at later age. Despite the fact that premature menopause has a profound effect on the health of women, there has been limited study on this issue. Therefore, this study attempted to determine the prevalence and factors associated with premature menopause among 302 557 women aged 25-39 years in India.

METHODS

This study utilized secondary data from the fourth round of the National Family Health Survey-IV (NFHS-4), conducted during 2015-2016 in India. Descriptive statistics and multinomial logistic regression were used for statistical analyses of the data.

RESULTS

The results revealed that the prevalence of premature menopause in this sample of Indian women was 3.7%, out of which 2.1% of women had experienced natural premature menopause, whereas 1.7% had surgical premature menopause. The prevalence of premature menopause was highest in the southern region of India. Factors like age, education, wealth index, place of residence, smoking status, children ever born, age at first birth, use of hormonal contraception, sterilization, and body mass index were found to be associated with premature menopause in India.

CONCLUSION

A sizeable proportion of women in India are attaining menopause prematurely. Furthermore, the percentage and likelihood of experiencing premature menopause are relatively high among rural women, women with higher parity, early age at childbearing, and women who smoke.

Prevalence of premature ovarian insufficiency and its determinants in Iranian populations: Tehran lipid and glucose study

BACKGROUND

Premature ovarian insufficiency (POI) considered as a concerning health issue for women of reproductive age. In this study we aim to estimate the prevalence of POI and assessing the influential factors.

METHODS

Data was obtained from Tehran lipid and glucose study (TLGS). All eligible post-menarcheal female participants of the TLGS, ages 20-65, were recruited (n = 6521). Participants were followed for the event of menopause, and age at menopause was recorded. Kaplan Meier analysis was applied to estimate mean and median for age at menopause. Weibull accelerated failure time survival regression model (AFT), was applied to assess influential determinants of POI. Conditional probability approach was used to provide estimation for prevalence of POI.

RESULTS

In this population-based study, the prevalence of POI (menopause age < 40 years) and early menopause (menopause age < 45 years) were estimated 3.5% and 24.6%, respectively. AFT model showed that in comparison to normal weight women, time to menopause was decreased by - 0.09 year (95% CI - 0.27, - 0.01, p = 0.023) and - 0.03 year (95% CI - 0.05, - 0.02, p = 0.000) in underweight and overweight women, respectively. Moreover, time to natural menopause was increased by 0.12 year (95% CI 0.07 to 0.17, p = 0.000) in women used oral contraceptives for > 6 months.

CONCLUSION

About one quartile of Iranian women experienced menopause at an age less than 45, especially the non-normal weight ones; this high prevalence is a critical public health concerns that needs to be addressed by health policy makers.

The Effects of Negative Elements in Environment and Cancer on Female Reproductive System

With the development of human society, factors that contribute to the impairment of female fertility is accumulating. Lifestyle-related risk factors, occupational risk factors, and iatrogenic factors, including cancer and anti-cancer treatments, have been recognized with their negative effects on the function of female reproductive system. However, the exact influences and their possible mechanism have not been elucidated yet. It is impossible to accurately estimate the indexes of female fertility, but many researchers have put forward that the general fertility has inclined through the past decades. Thus the demand for fertility preservation has increased more and more dramatically. Here we described some of the factors which may influence female reproductive system and methods for fertility preservation in response to female infertility.

Smoke, alcohol and drug addiction and female fertility

BACKGROUND

Considerable interest has been gathered on the relevant impact of preventable factors, including incorrect lifestyle and unhealthy habits, on female fertility. Smoking, alcohol and addictive drugs consumption represent a major concern, given the broad range of diseases which might be favored or exacerbated by these dependable attitudes. Despite the well-characterized effects of prenatal exposure on pregnancy outcomes and fetus health, a substantial proportion of women of reproductive age is still concerned with these habits. At present, the impact of smoke, alcohol and addictive drugs on women fertility, and, particularly, the specific targets and underlying mechanisms, are still poorly understood or debated, mainly due to the scarcity of well-designed studies, and to numerous biases.

OBJECTIVE

The current review will provide a comprehensive overview of clinical and experimental studies in humans and animals addressing the impact of smoke, alcohol and addictive drugs on female fertility, by also embracing effects on ovary, oviduct, and uterus, with particular reference to primary endpoints such as ovarian reserve, steroidogenesis, ovulation and menstrual cycle, oviduct function and uterus receptivity and implantation. A brief focus on polycystic ovary syndrome and endometriosis will be also included.

METHODS

A Pubmed literature search was performed with selected keywords; articles were individually retrieved by each author. No limitation was set for publication date. Articles in languages other than English were excluded. Additional articles were retrieved from references list of selected manuscripts.

RESULTS AND CONCLUSIONS

Currently, the most consistent evidences of a detrimental effect of smoke, alcohol and addictive drugs on specific domains of the female reproductive function are provided by experimental studies in animals. Overall, clinical studies suggest that smoking is associated to decreased fertility, although causal inference should be further demonstrated. Studies addressing the effect of alcohol consumption on female fertility provide conflicting results, although the majority reported lack of a correlation. Extremely scarce studies investigated the effects of addictive drugs on female fertility, and the specific actions of selected drugs have been difficult to address, due to multidrug consumption.

The global prevalence of primary ovarian insufficiency and early menopause: a meta-analysis

Objective: The aim of this study was to estimate the global prevalence of primary ovarian insufficiency (POI) and early menopause (EM). Methods: A comprehensive literature search was performed in several databases to retrieve relevant English articles published between 1980 and 2017. To assess the methodological quality of the studies, the Newcastle-Ottawa Scale was used. The heterogeneity of results across the studies was assessed using Cochran's Q test and quantified by the I² statistic. Prevalence estimates of all studies were pooled using a random-effects meta-analysis model at a confidence level of 95%. Results: A total of 8937 potentially relevant articles were identified from the initial searches. Thirty-one studies met the inclusion criteria and were included in this meta-analysis. The pooled prevalence of POI and EM was calculated as 3.7% (95% confidence interval: 3.1, 4.3) and 12.2% (95% confidence interval: 10.5, 14), respectively. The prevalence of POI was higher in medium and low Human Development Index countries. The prevalence trend did not change over time. Conclusion: The prevalence of POI and EM in women is considerable. The results of this study could contribute to consciousness-raising of health policy-makers toward the necessity of prioritizing, planning, and allocating health resources as preventive and treatment interventions for these women.

Effects of oral contraceptives on ovulation induction in in vitro fertilization patients with premature ovarian insufficiency

OBJECTIVE

To report a case series of in vitro fertilization patients with premature ovarian insufficiency, who were treated with oral contraceptives to reduce follicle stimulating hormone levels.

METHOD

This was a consecutive case series in a tertiary teaching hospital in China. Twenty-two women with refractory and idiopathic premature ovarian insufficiency were administered a drospirenone/ethinylestradiol oral contraceptive orally. The main outcome measures were the number of oocytes retrieved and the number of embryos frozen.

RESULTS

There were total 106 oral contraceptive treatment cycles and 53 oocyte retrieval cycles in 20 patients (91%, 20/22; 2.4 cycles per woman, 53/22). The total number of oocytes retrieved was 48 in 17 patients (77%, 17/22; 2.2 oocytes per woman, 48/22), and the total number of embryos frozen was 33 in 16 patients (73%, 16/22; 1.5 embryos per woman, 33/22).

CONCLUSION

Oral contraception may be an effective method to induce ovulation for some patients with premature ovarian insufficiency.

Environmental pollutants, a possible etiology for premature ovarian insufficiency: a narrative review of animal and human data

BACKGROUND

Because only 25% of cases of premature ovarian insufficiency (POI) have a known etiology, the aim of this review was to summarize the associations and mechanisms of the impact of the environment on this pathology. Eligible studies were selected from an electronic literature search from the PUBMED database from January 2000 to February 2016 and associated references in published studies. Search terms included ovary, follicle, oocyte, endocrine disruptor, environmental exposure, occupational exposure, environmental contaminant, pesticide, polyaromatic hydrocarbon, polychlorinated biphenyl PCB, phenol, bisphenol, flame retardant, phthalate, dioxin, phytoestrogen, tobacco, smoke, cigarette, cosmetic, xenobiotic. The literature search was conducted in accordance with the Preferred Reporting Items for Systematic Reviews and Meta-Analyses (PRISMA) guidelines. We have included the human and animal studies corresponding to the terms and published in English. We have excluded articles that included results that did not concern ovarian pathology and those focused on ovarian cancer, polycystic ovary syndrome, endometriosis or precocious puberty. We have also excluded genetic, auto-immune or iatrogenic causes from our analysis. Finally, we have excluded animal data that does not concern mammals and studies based on results from in vitro culture. Data have been grouped according to the studied pollutants in order to synthetize their impact on follicular development and follicular atresia and the molecular pathways involved. Ninety-seven studies appeared to be eligible and were included in the present study, even though few directly address POI. Phthalates, bisphenol A, pesticides and tobacco were the most reported substances having a negative impact on ovarian function with an increased follicular depletion leading to an earlier age of menopause onset. These effects were found when exposure occured at different times throughout the lifetime from the prenatal to the adult period, possibly due to different mechanisms. The main mechanism seemed to be an increase in atresia of pre-antral follicles.

CONCLUSION

Environmental pollutants are probably a cause of POI. Health officials and the general public must be aware of this environmental effect in order to implement individual and global preventive actions.

Prevalence of premature ovarian failure in patients with systemic lupus erythematosus

OBJECTIVE

To estimate the prevalence of premature ovarian failure (POF) and its associated factors in patients with systemic lupus erythematosus (SLE).

METHODS

Cross-sectional study including consecutive SLE women <60 years of age attending a rheumatology clinic. A face-to-face interview was undertaken to obtain demographic, gynaecological and lupus characteristics. Additional rheumatologic and endocrine data were retrieved from patients' medical records. POF prevalence was estimated in the study sample and in a subgroup of patients aged <40 years at interview. Associations between POF and selected variables were assessed by logistic regression analyses.

RESULTS

A total of 961 patients were analysed. Prevalence of POF, secondary amenorrhea of known cause, menopause and hysterectomy were 5.4%, 0.8%, 7.8% and 4.4%, respectively. In 674 (70%) patients who had not been exposed to cyclophosphamide (CYC) the prevalence of POF was 0.6%. Disease activity over time (OR 1.4 (CI 95% 1.0-1.8, p < 0.05)) and CYC treatment (OR 5.9 (CI 95% 1.8-18.8, p < 0.01)) were associated with higher prevalence. Association between POF and endocrine autoimmune diseases was not found.

CONCLUSIONS

In the absence of CYC treatment, the prevalence of POF in lupus patients is consistent with that reported in the general population. The existence of autoimmune processes at the ovary seems unlikely in most lupus patients.

Spanish consensus on premature menopause

INTRODUCTION

While we recognise that the term premature menopause is more accepted by most non-specialist health care providers and by the general population, 'primary ovarian insufficiency' (POI) is currently considered the most apposite term to explain the loss of ovarian function, because it better explains the variability of the clinical picture, does not specify definitive failure, and highlights the specific ovarian source. Its pathogenesis involves a congenital reduction in the number of primordial follicles, poor follicle recruitment, or accelerated follicular apoptosis. However, its cause is unknown in most cases.

AIM

This guide analyses the factors associated with the diagnosis and treatment of POI and provides recommendations on the most appropriate diagnostic and therapeutic measures for women under 40 years of age who experience POI.

METHODOLOGY

A panel of experts from various Spanish scientific societies related to POI (Spanish Menopause Society, Spanish Fertility Society, and Spanish Contraception Society) met to reach a consensus on these issues.

RESULTS

Hormonal therapy (HT) is considered the treatment of choice to alleviate the symptoms of hypoestrogenism and to prevent long-term consequences. We suggest that HT should be continued until at least age 51, the average age at natural menopause. The best treatment to achieve pregnancy is oocyte/embryo donation. If a patient is to undergo treatment that will reduce her fertility, she should be informed of this issue and the available techniques to preserve ovarian function, mainly vitrification of oocytes.

An update on primary ovarian insufficiency

Primary ovarian insufficiency (POI) occurs in about 1% of female population under the age of 40, leading to reproductive problems, an earlier encounter with menopausal symptoms, and complicated diseases. There are three presumable mechanisms involved in the development of POI, namely apoptosis acceleration, follicular maturation blocking and premature follicle activation, through the following studied causes: (i) chromosomal abnormalities or gene mutations: mostly involve X chromosome, such as FMR1 premutation; more and more potentially causal genes have been screened recently; (ii) metabolic disorders such as classic galactosaemia and 17-OH deficiency; (iii) autoimmune mediated ovarian damage: observed alone or with some certain autoimmune disorders and syndromes; but the specificity and sensitivity of antibodies towards ovary are still questionable; (iv) iatrogenic: radiotherapy or chemotherapy used in cancer treatment, as well as pelvic surgery with potential threat to ovaries' blood supply can directly damage ovarian function; (v) virus infection such as HIV and mumps; (vi) toxins and other environmental/lifestyle factors: cigarette smoking, toxins (e.g., 4-vinylcyclohexene diepoxide), and other environmental factors are associated with the development of POI. The etiology of a majority of POI cases is not identified, and is believed to be multifactorial. Strategies to POI include hormone replacement and infertility treatment. Assisted conception with donated oocytes has been proven to achieve pregnancy in POI women. Embryo cryopreservation, ovarian tissue cryopreservation and oocyte cryopreservation have been used to preserve ovarian reserve in women undergoing cancer treatments.

Early menopause association with employment, smoking, divorced marital status and low leptin levels

AIMS

The aims of this study were (1) to investigate the determining risk factors related to early menopause and (2) to compare the relationships between demographic characteristics and hormonal status and leptin levels in subjects with early (no surgical) and natural menopause.

STUDY DESIGN

The prospective study was conducted on 500 women with early and 2700 women with natural menopause. Detailed information was collected about their employment status, past and present smoking habits, coffee and alcohol use, educational level and other factors relevant to health. Thirty participants with early menopause and 30 participants with natural menopause were evaluated for hormone and leptin levels.

RESULTS

Employment status (OR: 1.94), current smoking (OR: 1.80) and divorced marital status (OR: 1.79) were found to be significant risk factors for early menopause. Mean levels of leptin in natural and early menopause were measured 11.40 ± 4.1 ng/ml and 8.01 ± 3.9 ng/ml, respectively (p = 0001). Leptin levels in the early (r = 0.765, p = 0.001) and natural (r = 0.750, p = 0.001) menopause subjects correlated positively with oestradiol (E2) levels.

CONCLUSION

This study shows that early onset of menopause is correlated with smoking, employment status, divorced marital status and lower leptin levels.

The association between educational level and age at the menopause: a systematic review

OBJECTIVES

To evaluate the association between educational level and age at menopause, and to describe the potential mechanisms involved.

METHODS

A systematic review of the literature was undertaken to evaluate this question. Educational level, which is considered one of the best socioeconomic indicators, was evaluated in this review as an exposure factor leading menopause to occur at an earlier age. The electronic search strategy was developed specifically for the different databases considered and through cross-referencing. After initially identifying 795 papers, 56 of them were selected for evaluation of the complete text.

RESULTS

In the end, our systematic review included 25 papers covering 29 studies. In 75.9% of the studies evaluated in this review, there was a weak association (statistically significant in 45%) between lower educational level and earlier age of the menopause. The various methodological differences between the studies were unable to substantially influence the results. The way in which educational level was measured and the methodology for comparing strata differed greatly. The complexity of socioeconomic level mechanisms on menopause imposed limitations on the conclusions from this study.

CONCLUSIONS

No unequivocal evidence for the existence of an association between educational level and age at menopause was found through this review.

Risk factors for type 2 diabetes in women attending menopause clinics in Italy: a cross-sectional study

OBJECTIVE

To analyze risk factors for type 2 diabetes among women attending menopause clinics in Italy for counselling about the menopause.

SUBJECTS

Women attending a network of first-level outpatient menopause clinics in Italy for general counselling about menopause or treatment of menopausal symptoms.

METHODS

Cross-sectional study with no exclusion criteria. Type 2 diabetes was defined according to National Diabetes Data Groups Indications and the fasting blood glucose at an oral glucose tolerance test within the previous year.

RESULTS

Out of the 44 694 considered in this analysis, 808 had a diagnosis of diabetes type 2 (1.8%). In comparison with women aged < 50 years, the multivariate odds ratios (OR) of type 2 diabetes were 1.31 (95% confidence interval (CI), 0.99-1.74) for women aged 50-52 years, 1.66 (95% CI, 1.27-2.17) at 53-56 years and 2.84 (95% CI, 2.20-3.67) in women aged > or = 57 years. Type 2 diabetes was less frequently reported in more educated women (OR high school/university vs. primary school = 0.44 (95% CI, 0.36-0.55)). Being overweight was associated with an increased risk of type 2 diabetes. In comparison with women reporting a low level of physical activity, the multivariate OR of type 2 diabetes was 0.67 (95% CI, 0.54-0.84) for women reporting regular physical activity. In comparison with premenopausal women, the multivariate OR of type 2 diabetes was 1.38 (95% CI, 1.03-1.84) in women with natural menopause. This finding was present also after allowing for the potential confounding effect of age. The multivariate OR of diabetes for users of hormonal replacement therapy was 0.58 (95% CI, 0.46-0.73).

CONCLUSIONS

This large cross-sectional study suggests that postmenopausal women are at higher risk of type 2 diabetes after allowance for the effect of age. Other main determinants of risk of type 2 diabetes in women around menopause were low socioeconomic status and being overweight. Diabetes was found less frequently in those taking hormone replacement therapy.

Does participation in an epidemiological study improve appropriate prescription of screening mammography for asymptomatic women?

BACKGROUND

To analyze the effect of participating in an epidemiological study on quality of care (i.e., appropriate prescription of mammographic screening), we have analyzed data collected in the framework of a cross-sectional study conducted in Italy among women attending menopause clinics.

METHODS

In 1997, a large cross-sectional study was organized on the characteristics of women who attended a network of first-level outpatient clinics for general counseling about menopause or treatment of menopausal symptoms. Women consecutively observed during the study were eligible, and the protocol did not set any exclusion criteria. All women who agreed to participate underwent a gynecological examination and were asked about their general characteristics and lifestyle habits, reproductive and menstrual history, and selected medical history. Laboratory and instrumental tests were required on clinical grounds; the protocol did not consider any test mandatory for all women, but all centers were asked to collect information on the examinations prescribed as routine clinical practice. The study began in 1997 in 25 centers. By March 1999, the number of centers had increased to 268 of which 63 were in the north, 81 in the center, and 124 in the south of Italy. Fewer than 3% of eligible women refused to participate. The study included 48,444 women. The present analysis looked at current attitudes toward screening mammography (SM) in asymptomatic women, as prescribed by gynecologists in menopausal centers in Italy.

RESULTS

A SM was correctly requested in 55.6% of women who entered the study during the second semester of 1997. This rose to 72.8% by July-August 2000. The correct prescription of a SM was slightly higher in current users of hormonal replacement therapy (HRT) and lower in women aged 45-50 years, the differences being significant (P < 0.05).

CONCLUSIONS

These results show that appropriate requests for SM increased in centers participating in a collaborative epidemiological study on menopause in Italy over a 3-year period.