Determinants of age at menopause in Italy: results from a large cross-sectional study. ICARUS Study Group. Italian Climacteric Research Group Study

OBJECTIVE: To identify the determinants of age at menopause in an Italian population, using data from the Italian Climacteric Research Group Study (ICARUS). METHODS: ICARUS is a prospective study of the effect of menopause on women's health that has been running in menopause clinics throughout Italy since 1995. A total of 4300 women with spontaneous menopause, aged 55 years or more and observed for the first time at the participating centres are included in the present analysis. RESULTS: The mean age at menopause in the total population was 50.9 years. After taking into account potential covariates, the women reported smoking, had a slightly lower mean age at menopause than non smokers 50.4 versus 50.9 years; P = 0.01. The mean age at menopause in nulliparae was 50.0 years, and, respectively 50.4, 50.6, 50.9, 51.2 and 50.9 years in those reporting 1, 2, 3, 4 and 5 or more births (P < 0.01). A low body mass index and an early age at menarche were associated with early menopause in the crude analysis, but these associations disappeared after taking into account the confounding factors. CONCLUSIONS: This study offers an estimate of the mean age at menopause of women attending menopause clinics in Italy, on the basis of the data obtained from a large sample. It also indicates that smoking and nulliparity are associated with early menopause.     

Risk factors for clinically diagnosed uterine fibroids in women around menopause

OBJECTIVE: We analysed the risk factors for clinically diagnosed uterine fibroids in women attending menopause clinics in Italy. METHODS: Between 1997 and 2003 we conducted a large cross-sectional study on the characteristics of women around menopause attending a network of first-level outpatient menopause clinics in Italy for general counselling about menopause or treatment of menopausal symptoms. A total of 85,967 non-hysterectomized women not reporting myomectomy entered the study; 2239 had a diagnosis of uterine fibroids. A woman was defined as having uterine fibroids if she had at gynecological examination an enlarged uterus (2 months of gestation or more) and a clinical diagnosis of fibroids. In 769 cases was performed in ultrasound examination which confirmed the diagnosis. RESULTS: In comparison with women with a body mass index (BMI) <22, the multivariate ORs for BMI 26 or more were 1.30 (95% CI, 1.09-1.55) for cases with clinical diagnosis, and 1.29 (95% CI, 1.01-1.45) for women with ultrasonographic diagnosis. In comparison with premenopausal women, the multivariate OR for clinically detected fibroids was 0.63 (95% CI, 0.55-0.72) for post-menopausal ones. The risk of fibroids was lower in parous women than in nulliparous ones, and the risk decreased with number of births regardless the type of diagnosis. CONCLUSION: This study confirms in a large sample that parity is the main protective factor for the development of fibroids. Overweight increases the risk.     

Menopausal status, hormone replacement therapy use and risk of self-reported physician-diagnosed osteoarthritis in women attending menopause clinics in Italy

OBJECTIVE: In order to offer data on the association between menopausal status, hormone replacement therapy use and risk of self-reported physician-diagnosed osteoarthritis (OA) in women around menopause, we analyzed information collected in the framework of a large epidemiological study conducted in Italy. METHODS: Since 1997, a large cross sectional study has been conducting on the characteristics of women around menopause attending a network of first level outpatients menopause clinics in Italy for general counseling about menopause or treatment of menopausal symptoms. Eligible for the study were women consecutively observed at the participating centers. Up to March 2000, a total of 42464 women (mean age 53 years) were observed. Women were asked, using the same questionnaire, about their general characteristics and habits, and if they suffer of OA diagnosed by a physician requiring medical or surgical treatment. RESULTS: A total of 12521 women reported OA. The risk of OA increased with body mass index (BMI), the odds ratio, OR, being for BMI>or equal to 27 versus <24, 1.56 (95%CI 1.47-1.64). The risk increased with a history of osteoporosis/osteopenia (OR 1.65, 95%CI 1.57-1.74) and was lower in more educated women (OR high school/university degree vs. primary school degree 0.79, 95%CI 0.75-0.84). Considering menopausal status, women in spontaneous or surgical menopause were, at increased risk of OA (OR 1.13, 95%CI 1.07-1.21, and 1.18, 95%CI 1.08-1.28, respectively, in women in surgical and spontaneous menopause). No clear relationship, however, emerged with age at menopause. Ever hormonal replacement therapy users were at decreased risk of OA, the OR being for ever users in comparison with never 0.73 (95%CI 0.69-0.78). CONCLUSION: This analysis gives some epidemiological support to the hypothesis that estrogen deficiency may increased the risk of OA.     

The timing of natural menopause in Poland and associated factors

OBJECTIVES: The outcome of interest was the assessment of age at natural menopause and the variables hypothesized as covariates of age at menopause were indicators of demographic and social status, characteristics of the reproductive history and lifestyle behaviour. METHODOLOGY: Seven thousand one hundred and eighty-three women from all social strata of non-clinical population, and aged between 35 and 65 years were investigated in cross-sectional survey across Poland in 2000-2004. The demographic, social, lifestyle behaviour and reproductive history aspects of the menopause-specific questionnaire were examined. The non-parametric Kaplan-Meier cumulative survivorship estimates were used to assess the timing of natural menopause. Univariate and multivariate Cox proportional hazards regression models were used to assess the association of age at natural menopause with factors of interest and to estimate relevant relative risk (the hazard ratio) for earlier age at menopause. RESULTS: The overall median age at natural menopause was 51.25 years; 25th percentile 49; 75th percentile 54 years. Temporal changes in age at menopause were not demonstrated in the sample (p=0.9 for differences among age cohorts). Univariate Cox models were first fitted to the age at natural menopause for all covariates singly. The findings revealed that marital status, living environment, employment, BMI, age at first live birth delivered by a woman, breastfeeding, physical activity, smoking amount, and consumption of alcohol were not associated with age at menopause (p>0.05). The multiple Cox model revealed that early menarche, short menstrual cycle length, smoking cigarettes, a low level of education, and a negative health perception were associated with younger age at menopause (p<0.01). Use of oral contraceptives and parity were associated with later menopause (p<0.01). CONCLUSION: The present study provides an estimate of median age at natural menopause in Poland that may be used as a measure of health for the growing number of Polish women whose survival is calculated at 30 years after menopause. This study has revealed that the pattern of relationship between age at menopause and the study factors reflects its population-specific character for its social and cultural backgrounds, socio-economic status, and social behaviours.     

Season of birth influences the timing of menopause

BACKGROUND: Seasons may influence prenatal growth and future fertility. This study investigated whether season and month of birth influenced the timing of menopause in a group of women attending three Italian menopause clinics. METHODS and RESULTS: Age at menopause of 2822 post-menopausal women (>12 months of amenorrhoea) was stratified by month and season of birth. Mean age at menopause was 49.42 years (SEM: 0.78 years). Menopause occurred earlier for women born in the spring (age 49.04+/-0.15 years) than in the autumn (49.97+/-0.14 years). The earliest menopause was found in women born in March (48.9+/-0.25 years) and the latest in women born in October (50.3+/-0.25 years). The effect of season of birth on age at menopause remained even when considering factors that in our analysis were capable of significantly interfering with the timing of menopause, such as age at menarche, body mass index, smoking habit, level of education and type of job. CONCLUSIONS: Taking into consideration the retrospective design of the study, and a possible recall bias, the present data seem to suggest that environmental factors linked to seasons are capable of interfering with the timing of a woman's ovarian exhaustion by an action exerted in the prenatal period.     

The influence of Nos3 polymorphisms on age at menarche and natural menopause

OBJECTIVE: Deficiency of the gene encoding endothelial nitric oxide synthase, i.e. Nos3, has been reported to be associated with late menarche, reduced ovulation rates, fewer deliveries, and earlier onset of menopause in a mouse model. METHODS: We assessed the Glu298Asp and the T-786C polymorphisms of Nos3 in 87 consecutive healthy postmenopausal women by pyro- and capillary-sequencing, respectively. Results were correlated with age at menarche and natural menopause, number of miscarriages and live births, as well as body mass index (BMI) and smoking habits. RESULTS: Allelic frequencies of the Glu298Asp polymorphism of Nos3 were 121 (69.5%) and 53 (30.5%) for the wild-type G allele and the mutant T allele, respectively. Forty-one women (47.1%) were homozygote wild-type (G/G), 39 (44.9%) were heterozygote (G/T), and 7 (8.0%) were homozygote mutant (T/T). Allelic frequencies of the T-786C polymorphism of Nos3 were 105 (60.6%) and 69 (39.4%) for the wild-type T allele and the mutant C allele, respectively. Thirty-three women (38.0%) were homozygote wild-type (T/T), 39 (45.1%) were heterozygote (T/C), and 15 (16.9%) were homozygote mutant (C/C). Presence of at least one mutant allele of the Glu298Asp or the T-786C polymorphisms of Nos3 were not associated with age at menarche, natural menopause, and number of miscarriages and deliveries. BMI above 27 kg/m2 and smoking were associated with earlier onset of natural menopause (47.8 years versus 50.2 years (P = 0.01) and 46.8 years versus 49.8 years (p = 0.02)). CONCLUSIONS: Our data show that smoking and increased BMI, but not Glu298Asp or the T-786C polymorphisms of Nos3, are associated with an early onset of natural menopause.     

The age at menopause and associated factors at the health center area in Ankara, Turkey

OBJECTIVES: This study is performed in one health center area in Ankara, Turkey on a women population of 50-65 years in order to demonstrate menopausal status of women, age at menopause and factors related with the age at menopause. METHODS: This is a cross-sectional study which has been performed on a women population of 50-65 years. The local population was 17,153 in this area by 2001. All of the household determining forms are screened in order to detect the all of the women who were in 50-65 years group, then name and addresses of the these women's are listed. There were 1089 women aged 50-65 years who were constituting 7% of the population. After choosing the first name randomly from the list of the women, 1/3 systematic sampling method was used and, the number of the women in the sampling was 363 (95% C.I., +/-5% S.E.). The response rate among those eligible women who were contactable during the study was 99% (360/363). Data were collected by interviews through questionnaires. The questionnaire consisted of a series of questions concerning age at menopause, socioeconomic status, age at menarche, age at first pregnancy, regularity of menstrual cycles, parity, duration of breast feeding, use of OCs, BMI, smoking habit, age at menopause of the mother and the sister. Chi-square and t-test methods were used for statistical analyses. RESULTS: 4.2% of the women were in premenopause, 13.3% were in perimenopause, 72.8% were in natural menopause and 9.7% were in surgical menopause. Average age at natural menopause was 47+/-4.2 years. Education, age at menarche, smoking, age at menopause of the mother and the sister were found to be related with the age at menopause. CONCLUSIONS: Ninety-six percent of the women over age of 50 years, are at menopause or perimenopause. The results of this study suggest that, for factors of genetic and age at menarche, there are not many possibilities for the lifestyle changes that would modify age at menopause with the subsequent reduction in risk for chronic diseases, but daughters or sisters of women with an early menopause and women who smoked or less educated could be counselled with respect to family timing.     

Associations with age at natural menopause in Blackfeet women

This study seeks to determine the age at natural menopause and factors that may predict that age for Blackfeet women living on the reservation in Montana. Data were obtained from a probability sample of 150 women. Rates of surgical menopause among women who had experienced menopause were similar to those found in NHANES I for U.S. women. Median age at natural menopause by the status quo method (51.2 years) was comparable to that determined for other populations. Within the group of women who already had experienced natural menopause, age at menopause was associated in bivariate models with age at menarche (b = ?0.83 ± 0.44 years, P = 0.07), household income (b = 1.85 ± 0.71 years, P = 0.01), “ever use” of birth control (b = 4.52 ± 1.58 years, P = 0.008), “ever use” of oral contraceptives (b = 5.48 ± 1.91 years, P = 0.007), current or recent unemployment (b = 4.75 ± 1.97 years, P = 0.02), having been breastfed (b = ?6.93 ± 2.67 years), and educational attainment (ANOVA by tertiles of menopause age, mean 10.0 ± 3.6 years of education for earliest, 13.0 ± 2.2 years for latest, P = 0.04). In multivariate models, “ever use” of oral contraceptives, household income, and age at menarche remained significant predictors of age at menopause (R² = 0.33–0.35, P = 0.002–0.004), with household income modifying the effect of age at menarche (analysis of joint effects). The findings are discussed in the context of cohort experiences, examining implications for both early and later‐life influences on menopause age. Am. J. Hum. Biol. 13:512–520, 2001. © 2001 Wiley‐Liss, Inc.     

Body mass index trajectories and age at menopause in a British birth cohort

OBJECTIVE: This study investigates the influence of body mass index (BMI) at ages 15, 20, 26, 36, and 43, and of BMI trajectories from 20 to 36 years on the timing of menopause and hormone therapy (HT) use until age 57 years. METHODS: A nationally representative British cohort of 1583 women born in March 1946 with prospective data across the life course. RESULTS: By age 57, a total of 695 women had experienced natural menopause while 431 women had started HT prior to menopause. Cox regression models indicated no significant associations between BMI at any age, or BMI trajectory, and timing of natural menopause. At every age BMI was strongly (p< or =0.01) and linearly associated with age at HT use and BMI from 26 years onwards was associated with age at first event (menopause or HT use). Decreasing BMI was associated with earlier HT use at all ages. These associations were not accounted for by parity, cigarette smoking or childhood and adult social class. CONCLUSION: BMI across the reproductive lifespan did not influence age at menopause to an extent that would be clinically relevant for postmenopausal health. Lower BMI at all ages and underweight trajectory were related to an earlier start of HT. Further studies are required to understand whether such relationships are due to underweight women experiencing menopause earlier (and because of menopausal symptoms starting HT earlier) than heavier women, or having behavioural characteristics related to earlier HT use, independent of menopause.     

Effect of natural early menopause on bone mineral density

OBJECTIVES: Early menopause (EM) is included among the risk factors for osteoporosis. Several studies have shown that women with early menopause have lower bone mineral density (BMD) than those with normal expected age of menopause. The aim of our cross-sectional study was to investigate the effects of time of menopause on vertebral bone mass in healthy postmenopausal women and to evaluate if early menopause is a risk factor for lower vertebral BMD. METHOD: We studied 782 who had never received drugs acting on bone mass. The study population was divided into three groups: women with early, normal (NM), and late (LM) menopause. Our study population was further categorized in 5-year age segments between 45 and >75. RESULTS: The three groups examined did not differ for age, age at menarche, body mass index (BMI), and vertebral BMD, while there were significant differences in age at menopause and years since menopause. Our study showed that women with EM presented significantly lower vertebral BMD than NM and LM in 50-54 age segments. Beyond 55 years, EM, NM, and LM women had no differences in lumbar BMD values. CONCLUSIONS: In conclusion, controversial data demonstrated that the absolute amount of bone loss is greater after early menopause than after normal or late menopause, even if a slight effect of early menopause on bone mass cannot be excluded.     

Risk factors for high blood pressure in women attending menopause clinics in Italy

ObjectiveWe analysed risk factors for high blood pressure (BP) among women around menopause.MethodsEligible women were consecutively attending first-level outpatient menopause clinics in Italy for general counseling or treatment of menopausal symptoms. During the visit BP was measured three times. The mean of second and third of the three diastolic BP values for women was >90 mm of mercury and/or reporting any current pharmacological treatment for high BP were considered hypertensive. Out of 45,204 women who entered the study with information on blood pressure, 12,150 had high BP.ResultsThe odds ratios (OR) of high BP increased with age: in comparison with women aged <50 years, the multivariate OR were 1.44 (95% confidence interval (CI), 1.34–1.55), 1.61 (95% CI, 1.50–1.74) and 1.91 (95% CI, 1.77–2.06) in women aged 51–53, 54–57 and ≥58, respectively. Women with high BP were less educated than those without (OR education >12 versus <7 years, 0.79, 95% CI, 0.74–0.84). In comparison with women with a body mass index (BMI) <24, the multivariate ORs were 1.48 (95% CI, 1.39–1.57) and 2.56 (95% CI, 2.41–2.71) for women with BMI 24–26 and >26. In comparison with women reporting no regular physical activity, the multivariate OR of high BP was 0.93 (95% CI, 0.87–0.99) for women reporting regular activity. In comparison with peri-menopausal women, post-menopausal women were at increased risk (OR 1.14, 95% CI, 1.03–1.24) and the risk tended to increase with age at menopause. Current use of hormonal replacement therapy (HRT) was associated with a lower risk of high BP (OR 0.88, 95% CI, 0.84–0.94).ConclusionsThis large cross-sectional study suggests that, after taking into account the effect of age, post-menopausal women are at greater risk of high BP, but current HRT use slightly lowers the risk. Other determinants of high BP were low level of education, overweight, and low level of physical activity.     

Factors associated with the age of natural menopause and menopausal symptoms in Chinese women

ObjectiveTo investigate the factors associated with the age of natural menopause and menopausal symptoms in a large population of Chinese middle-aged women.Study designIn this cross-sectional study, a total of 20,275 women (40–65 years) attending health screening in Jiangsu Province of China were enrolled. A structured questionnaire was used to collect data of demographics, menopausal status, chronic diseases, reproductive history, etc. Also we evaluated the severity of menopausal symptoms by Kupperman menopause index (KMI).Main outcome measureMenopausal age and scorings of Kupperman menopause index.ResultsThe overall median age at natural menopause was 50 years. Lower educational level, poor economic status, lower body mass index (BMI), age at menarche less than 14 years, nulliparity and smoking were associated with earlier onset of natural menopause (P < 0.05). The most frequently symptoms in postmenopausal women were sexual problems (57.05%), muscle/joint pain (53.29%) and insomnia (51.02%), while fatigue, insomnia and muscle/joint pain were predominant symptoms in pre- and peri-menopausal women. After adjusting for confounding factors, logistic regression analysis revealed that women with poor educational background, low income, divorce, higher BMI, higher parity, smoking and chronic diseases presented higher KMI scores (P < 0.05).ConclusionThe study provided an estimate of median age at natural menopause in Chinese women. The main factors contributing to earlier onset of menopause and severity of menopausal symptoms were lower educational level, poor economic status, and smoking. Thus, this study provides important insights for physicians to prevent and treat menopause related symptoms.     

Hormone therapy and sleep quality in women around menopause

OBJECTIVE: To obtain data on sleep quality in women attending menopause clinics in Italy. DESIGN: A cross-sectional study was conducted on the sleep quality of postmenopausal women attending a network of first-level outpatient menopause clinics in Italy for general counseling about menopause or treatment of its symptoms. Eligible for the study were women observed consecutively during the study period with natural or spontaneous menopause.All participating centers enrolled women into the study who had never used hormone therapy (HT) (group 1, 819 women), current users of transdermal estrogens with or without progestins (group 2, 819 women), and current users of oral estrogens with or without progestins (group 3, 790 women). The women were asked about their quality of sleep using the Basic Nordic Sleep Questionnaire, their quality of life using the Short Form-12 questionnaire, and the intensity of hot flushes using a visual analogue scale. RESULTS: Women in groups 2 and 3 tended to report difficulties in sleeping less often than those in group 1. For example, never users of HT more frequently reported sleeping poorly and needed more time to sleep or had problems falling asleep; these differences were significant (P < 0.05). Otherwise, no difference emerged from the Basic Nordic Sleep Questionnaire between women in groups 2 and 3. CONCLUSIONS: This study gives support to the suggestion that HT improves the quality of sleep. The effect was similar in women taking oral or transdermal therapy with or without progestins.     

Factors associated with the age of natural menopause and menopausal symptoms in Chinese women

Objective

To investigate the factors associated with the age of natural menopause and menopausal symptoms in a large population of Chinese middle-aged women.

Study design

In this cross-sectional study, a total of 20,275 women (40–65 years) attending health screening in Jiangsu Province of China were enrolled. A structured questionnaire was used to collect data of demographics, menopausal status, chronic diseases, reproductive history, etc. Also we evaluated the severity of menopausal symptoms by Kupperman menopause index (KMI).

Main outcome measure

Menopausal age and scorings of Kupperman menopause index.

Results

The overall median age at natural menopause was 50 years. Lower educational level, poor economic status, lower body mass index (BMI), age at menarche less than 14 years, nulliparity and smoking were associated with earlier onset of natural menopause (P < 0.05). The most frequently symptoms in postmenopausal women were sexual problems (57.05%), muscle/joint pain (53.29%) and insomnia (51.02%), while fatigue, insomnia and muscle/joint pain were predominant symptoms in pre- and peri-menopausal women. After adjusting for confounding factors, logistic regression analysis revealed that women with poor educational background, low income, divorce, higher BMI, higher parity, smoking and chronic diseases presented higher KMI scores (P < 0.05).

Conclusion

The study provided an estimate of median age at natural menopause in Chinese women. The main factors contributing to earlier onset of menopause and severity of menopausal symptoms were lower educational level, poor economic status, and smoking. Thus, this study provides important insights for physicians to prevent and treat menopause related symptoms.     

Correlates of the age at natural menopause in Morocco

Primary objective : To determine the median age of natural menopause and factors associated with the timing of menopause in Morocco. Research design : A population-based sample of 299 women from Rabat, Morocco were interviewed using a semi-structured questionnaire. Methods and procedures : Logit analysis and logistic regression were used to estimate the median age and identify factors associated with the age at menopause. Main outcomes and results : The median age of natural menopause in Morocco is estimated to be 48.4 years (95% CI: 36.9, 70.3). Women who reported the onset of menstruation at age 11 or younger (OR = 2.84, 95% CI: 1.00, 8.10) had an earlier age at menopause than women who started menstruating at age 12 or older. Women who had ever used oral contraceptives were more likely to have a later age at menopause (OR = 0.55, 95% CI: 0.30, 1.00). The length of time a woman used oral contraceptives influenced the timing of the menopause in unadjusted models but after adjusting for the age at menarche the effect was no longer statistically significant. Marital status, parity, education level, and social class were not statistically associated with the age at menopause. Conclusions : The estimated age at natural menopause in Morocco is 1-3 years earlier than the median ages reported in industrialized countries and some developing countries. Factors that alter the frequency of ovulation or rate of follicular atresia appear to be important in determining the age at menopause.     

Correlates of the age at natural menopause in Morocco

PRIMARY OBJECTIVE: To determine the median age of natural menopause and factors associated with the timing of menopause in Morocco. RESEARCH DESIGN: A population-based sample of 299 women from Rabat, Morocco were interviewed using a semi-structured questionnaire. METHODS AND PROCEDURES: Logit analysis and logistic regression were used to estimate the median age and identify factors associated with the age at menopause. MAIN OUTCOMES AND RESULTS: The median age of natural menopause in Morocco is estimated to be 48.4 years (95% CI: 36.9, 70.3). Women who reported the onset of menstruation at age 11 or younger (OR = 2.84, 95% CI: 1.00, 8.10) had an earlier age at menopause than women who started menstruating at age 12 or older. Women who had ever used oral contraceptives were more likely to have a later age at menopause (OR = 0.55, 95% CI: 0.30, 1.00). The length of time a woman used oral contraceptives influenced the timing of the menopause in unadjusted models but after adjusting for the age at menarche the effect was no longer statistically significant. Marital status, parity, education level, and social class were not statistically associated with the age at menopause. CONCLUSIONS: The estimated age at natural menopause in Morocco is 1-3 years earlier than the median ages reported in industrialized countries and some developing countries. Factors that alter the frequency of ovulation or rate of follicular atresia appear to be important in determining the age at menopause.     

Polymorphisms of the CYP1B1 gene may be associated with the onset of natural menopause in Chinese women

The Cytochrome P450 1B1 (CYP1B1) is one of the major CYP450 enzymes catalyzing 4-hydroxylation, an important elimination step for estrogens. Relatively little is known, however, about the impact of this gene on the onset and cessation of menstruation, which are significant milestones in a woman's life and predictors of many hormone related diseases. In this report, we described the association of four SNPs in the CYP1B1 gene, Arg48Gly, Ala119Ser, Leu432Val, and Asp449Asp, with the ages of menarche and menopause, years of menstruation and total number of menstrual cycles. Included in the study were 1958 community controls from two recently completed population-based case-control studies of breast cancer and endometrial cancer. No association was observed between the CYP1B1 polymorphisms and the age of menarche among either pre- or post-menopausal women. Among the women who experienced natural menopause, the three non-synonymous SNPs were significantly associated with menopausal age, years of menstruation, and total number of menstrual cycles. The Gly and Ser alleles of Arg48Gly and Ala119Ser were associated with later menopause, more years of menstruation and more menstrual cycles, while women with allele Val at Leu432Val had a 0.9 year earlier menopause, 1.0 year shorter reproductive span, and 12.6 fewer menstrual cycles than those women without this allele. In conclusion, the results from this study suggested that CYP1B1 genetic polymorphisms may be associated with the natural onset of menopause.     

Increase in breast size after menopause: prevalence and determinants

OBJECTIVES: To determine the prevalence and determinants of increases in breast size after menopause. METHODS: Subjects were 1130 postmenopausal women, aged 54-71, participating in a population based breast cancer screening project, the DOM-project in Utrecht, The Netherlands. Questionnaire data on changes in breast size, parity, age at first childbirth, breast feeding, age at menarche, age at menopause, HRT use and usual weight between age 30 years and age at questionnaire were used. Weight and height were measured at three screening rounds and waist and hip circumference was measured once. RESULTS: 18.6% of the women reported that they had to buy a larger bra because of changes in breast size, whereas 1.7% reported that they had to buy a smaller bra. Weight gain, waist circumference, hip circumference, Quetelet's index at third screening, Quetelet's index at first screening, waist-to-hip ratio and years since menopause were significantly associated with increased breast size (odds ratios between 2.5 and 1.4) (all tests for trend P < 0.05), whereas age at menopause, HRT use, parity and age at menarche were modestly, though not significantly associated with increased breast size. Age, usual Quetelet's index, age at first childbirth and number of months of full breast feeding were not associated with increased breast size. CONCLUSION: About one in five women experienced an increase in breast size after menopause. The most important factor associated with such an increase was found to be weight gain.     

Premenopausal factors influencing premature ovarian failure and early menopause

OBJECTIVES: We conducted this study to examine premenopausal risk factors associated with premature ovarian failure (POF) and early menopause (EM) among Korean women. METHODS: A 73% of total women aged 30-69 at four districts in the KMCC (Korean Multi-center Cancer Cohort) was participated in this study during 2002-2003. We selected 137 POF and 281 EM cases who had menopause before age 40 and at age 40-44, respectively, and 1318 normal menopause (NM) controls that experienced menopause at age 45-60, and among them, selected idiopathic POF (n=84) and EM (n=261) after excluding surgical/medical menopause. We collected the information of premenopausal lifestyle and reproductive risk factors. Multivariate and polytomous logistic regression were used to estimate POF and EM risk and to differentiate POF and EM risk using ordinal and nominal scale. RESULTS: Cigarette smoking was associated with an increased risk of idiopathic POF (OR=1.82 [1.03-3.23]), whereas oral contraceptive use was associated with a reduced risk of natural EM (OR=0.62 [0.43-0.90]). Idiopathic POF risk by both factors differed from idiopathic EM risk (p-nominal<0.05). Factors related to ovulation, such as later menarche, irregular menstruation and longer breast feeding cumulatively reduced the risk of natural EM and POF (p-ordinal<0.05). In analysis including medical and surgical menopause, lung tuberculosis, hysterectomy, past cancers, and lower number of deliveries before menopause were associated with POF. CONCLUSIONS: Our findings indicate that etiology in POF development may partly differ from that in EM.