Factors associated with symptoms of poor mental health among women factory workers in China's supply chain.

OBJECTIVE: Foreign direct investment (FDI) to China has motivated increased labor migration to export processing zones (EPZs). Work environments with high occupational stress, such as production line jobs typical in EPZs, have been associated with adverse mental health symptoms. METHODS: A cross-sectional survey that examined occupational stress and symptoms of poor mental health was implemented among Chinese women factory workers in three electronic factories in the Tianjin Economic-Technological Development Area. Symptoms of mental health measured in the survey were hopelessness, depression, not feeling useful or needed, and trouble concentrating. Crude and adjusted prevalence odds ratios and their 95% confidence intervals were calculated with logistic regression. RESULTS: Responses were collected from 696 women factory workers. Participants were aged 18-56 years (mean 28 ± 5.8), 66% of whom were married and 25% of whom were migrants. Nearly 50% of participants reported at least one symptom of poor mental health. After adjusting for covariates associated with each outcome in the bivariate analysis, high job strain was associated with hopelessness (OR 2.68, 95% CI 1.58, 4.56), not feeling useful (OR 2.05, 95% CI 1.22, 3.43), and feeling depressed (OR 1.78, 95% CI 1.16, 2.72). CONCLUSION: This study expands on the international body of research on the well-being of women working in the global supply chain and provides evidence on the associations between occupational stressors, migration, and social support on symptoms of poor mental health among women workers. Future research to better understand and improve psychological health and to prevent suicide among workers in China's factories is critical to improve the health of China's labor force.

Patterns of violence and coercion with mental health among female and male trafficking survivors: a latent class analysis with mixture models.

AIMS: Human trafficking is a crime and a human rights violation that involves various and simultaneous traumatic events (sexual and physical violence, coercion). Yet, it is unknown how the patterning of violence and coercion affects the mental health of female and male trafficking survivors. METHODS: We conducted a cross-sectional study using a sample of 1015 female and male survivors of trafficking who received post-trafficking assistance services in Cambodia, Thailand or Vietnam. We assessed symptoms of anxiety and depression with the Hopkins Symptoms Checklist and symptoms of post-traumatic stress disorder (PTSD) with the Harvard Trauma Questionnaire. Violence was measured with questions from the World Health Organization International Study on Women's Health. Latent class analysis (LCA) was used to identify distinct patterns of violence and coercion in females and males. Novel multi-step mixture modelling techniques were employed to assess the association of the emergent classes with anxiety, depression and PTSD in females and males. RESULTS: LCA identified two distinct classes of violence and coercion experiences in females (class I: severe sexual and physical violence and coercion (20%); class II: sexual violence and coercion (80%)) and males (class I: severe physical violence and coercion (41%); class II: personal coercion (59%)). Females in class I had a two-fold increase in the odds of anxiety (OR = 2.10; 95% CI: 1.57-2.81) and PTSD (OR = 2.07; 95% CI: 1.03-4.17) compared with females in class II, but differences in the prevalence of anxiety, depression and PTSD were not significant when comparing males in class I to class II. CONCLUSIONS: Specific patterns of violence and coercion provide a more in-depth understanding of the role of gender in the experience of violence and coercion and its association with mental health in survivors of trafficking. This information could be useful to target comprehensive mental health services for female and male trafficking survivors.

Does AMH relate to timing of menopause? Results of an Individual Patient Data meta- analysis.

CONTEXT: Anti-Müllerian hormone based (AMH) age at menopause predictions remain cumbersome due to predictive inaccuracy. OBJECTIVE: To perform an Individual Patient Data (IPD) meta-analysis, regarding AMH based menopause prediction. DATA SOURCES: A systematic literature search was performed using PubMed, Embase and Cochrane databases. STUDY SELECTION: Prospective cohort studies regarding menopause prediction using serum AMH levels were selected by consensus discussion. DATA SELECTION: Individual cases were included if experiencing a regular cycle at baseline. Exclusion criteria were hormone use and gynecological surgery. DATA SYNTHESIS: 2596 women were included, 1077 experienced menopause. A multivariable Cox regression analysis assessed time to menopause (TTM) using age and AMH. AMH predicted TTM, however, added value on top of age was poor (age alone C-statistic 84%; age + AMH HR 0.66 95% CI 0.61-0.71, C-statistic 86%). Moreover, the capacity of AMH to predict early (≤45 years) and late menopause (≥55 years) was assessed. An added effect of AMH was demonstrated for early menopause (age alone C-statistic 52%; age + AMH HR 0.33, 95% CI 0.24-0.45, C-statistic 80%). A Weibull regression model calculating individual age at menopause revealed that predictive inaccuracy remained present and increased with decreasing age at menopause. Lastly, a check of non-proportionality of the predictive effect of AMH demonstrated a reduced predictive effect with increasing age. CONCLUSION: AMH was a significant predictor of TTM and especially of time to early menopause. However, individual predictions of age at menopause demonstrated a limited precision, particularly when concerning early age at menopause, making clinical application troublesome.

Association between changes in oestradiol and follicle-stimulating hormone levels during the menopausal transition and risk of diabetes.

AIM: To investigate the association between changes in oestradiol and follicle-stimulating hormone levels during the menopausal transition and incident diabetes. METHODS: We followed 1407 pre-menopausal women, aged 42-52 years at baseline, who experienced natural menopause, from baseline to the 12th annual follow-up visit in the Study of Women's Health Across the Nation (SWAN). Diabetes was defined based on fasting glucose level, medication use and self-report of physician diagnosis. Cox proportional hazards regression was used to evaluate the associations of incident diabetes with three components of the rate of change in hormones: the intercept (pre-menopausal levels) and two piece-wise slopes representing change during the early and late transition, respectively. RESULTS: During 15 years of follow-up, 132 women developed diabetes. After adjusting for potential confounders, a higher oestradiol intercept, but not its rate of change, was borderline significantly associated with lower risk of diabetes [hazard ratio for an interquartile range increase (75.2 pmol/L) 0.53, 95% CI 0.27-1.06]. For follicle-stimulating hormone, a greater rate of increase in the early transition, but not the intercept or late transition, was significantly associated with lower risk of diabetes [hazard ratio for an interquartile range increase (5.9 IU/L/year) 0.31, 95% CI 0.10-0.94]. CONCLUSIONS: Lower pre-menopausal oestradiol levels and a slower rate of follicle-stimulating hormone change during the early transition were associated with higher risk of developing diabetes. Given that obesity plays an important role in diabetes risk and in the levels and changes in oestradiol and follicle-stimulating hormone over the menopausal transition, weight control in earlier mid-life is important to prevent future diabetes development.

Bleeding patterns during the menopausal transition in the multi-ethnic Study of Women's Health Across the Nation (SWAN): a prospective cohort study.

OBJECTIVE: Previous studies describing menses duration and heaviness of flow during the menopausal transition (MT) have been short in duration and limited to white women. We estimated the frequency of and risk factors for prolonged bleeding, spotting and heavy bleeding during the MT in an ethnically diverse population. DESIGN: Prospective community-based cohort study. SETTING USA: southeastern Michigan, northern California and Los Angeles, California. POPULATION: A total of 1320 midlife women who participated in the Study of Women's Health Across the Nation (SWAN) Menstrual Calendar Substudy. Participants included African-American, white, Chinese, and Japanese women. METHODS: Women completed daily menstrual calendars from 1996 to 2006, and provided information on hormone therapy, smoking and physical activity. Annual measures included height and weight. Kaplan-Meier survival analysis and multivariable regression were used to analyse the data. MAIN OUTCOME MEASURES: Menses of 10+ days, spotting of 6+ days, heavy bleeding of 3+ days. RESULTS: At least three occurrences of menses 10+ days was reported by 77.7% (95% confidence interval [95% CI] 56.7-93.2), of 6+ days of spotting by 66.8% (95% CI 55.2-78.0) and of 3+ days of heavy bleeding by 34.5% (95% CI 30.2-39.2) of women. Menses of 10+ days, 6+ days of spotting, and 3+ days of heavy bleeding were associated with MT stage, uterine fibroids, hormone use and ethnicity. Body mass index was associated with 3+ days of heavy bleeding. CONCLUSIONS: These data provide clinicians and women with important information about the expected frequency of prolonged and heavy bleeding and spotting during the menopausal transition that may facilitate clinical decision making.

Oral contraceptive use and risk of vulvodynia: a population-based longitudinal study.

OBJECTIVE: To assess whether the risk of vulvodynia is associated with previous use of oral contraceptives (OCs). DESIGN: Longitudinal population-based study. SETTING: Four counties in south-east Michigan, USA. POPULATION: A population-based sample of women, aged 18 years and older, enrolled using random-digit dialling. METHODS: Enrolled women completed surveys that included information on demographic characteristics, health status, current symptoms, past and present OC use, and a validated screen for vulvodynia. The temporal relationship between OC use and subsequent symptoms of vulvodynia was assessed using Cox regression, with OC exposure modelled as a time-varying covariate. MAIN OUTCOME MEASURE: Vulvodynia, as determined by validated screen. RESULTS: Women aged <50 years who provided data on OC use, completed all questions required for the vulvodynia screen, and had first sexual intercourse prior to the onset of vulvodynia symptoms were eligible (n = 906). Of these, 71.2% (n = 645) had used OCs. The vulvodynia screen was positive in 8.2% (n = 74) for current vulvodynia and in 20.8% (n = 188) for past vulvodynia. Although crude cross-tabulation suggested that women with current or past vulvodynia were less likely to have been exposed to OCs prior to the onset of pain (60.7%), compared with those without this disorder (69.3%), the Cox regression analysis identified no association between vulvodynia and previous OC use (HR 1.08, 95% CI 0.81-1.43, P = 0.60). This null finding persisted after controlling for ethnicity, marital status, educational level, duration of use, and age at first OC use. CONCLUSION: For women aged <50 years of age, OC use did not increase the risk of subsequent vulvodynia.

Cervical cancer screening among Michigan women: 'The Special Cancer Behavioral Risk Factor Survey', 2004-2008.

The burden of cervical cancer remains greater among minority women. The purpose of this study was to evaluate racial/ethnic disparities in cervical cancer screening among minority women in Michigan. Data from 8,023 women (≥ 40 years) surveyed in the 2004-2008 Michigan Special Cancer Behavioral Risk Factor Survey were used to assess racial/ethnic differences in cervical cancer screening, knowledge and beliefs. Unexpectedly, African-American and Hispanic women reported being screened for cervical cancer at rates similar to, or higher than, Whites. Women demonstrated limited knowledge of cervical cancer risk factors and its signs/symptoms. Most minority women were more likely than Whites to believe in the importance of cervical screening, with Hispanic women more likely to support HPV vaccination. Differential utilisation of screening does not explain the disproportionately high rates of cervical cancer among minorities. Future research should examine disparities in the follow-up of abnormal cervical results and receipt of treatment.

Racial/ethnic differences in hepatic steatosis in a population-based cohort of post-menopausal women: the Michigan Study of Women's Health Across the Nation.

AIMS: The prevalence of hepatic steatosis may differ between post-menopausal African-American women and non-Hispanic white women and by sex hormone binding globulin level. We examined prevalence of hepatic steatosis by race/ethnicity and associations with sex hormone binding globulin. METHODS: Participants included post-menopausal women who underwent hepatic ultrasound (n = 345) at the Michigan site of the Study of Women's Health Across the Nation, a population-based study. We examined hepatic steatosis prevalence by race/ethnicity and used logistic regression models to calculate the odds of hepatic steatosis with race/ethnicity and sex hormone binding globulin, after adjustment for age, alcohol use, waist circumference, high density lipoprotein cholesterol, triglycerides, systolic blood pressure and use of medications reported to lower intrahepatic fat. RESULTS: Fewer African-American women than non-Hispanic white women had hepatic steatosis (23 vs. 36%, P = 0.01). African-American women had lower triglyceride and low-density lipoprotein cholesterol levels, but higher blood pressure and follicle-stimulating hormone levels (P < 0.05). In the optimal-fitting multivariable models, women in the highest tertile of sex hormone binding globulin (60.2-220.3 nmol/l) had a lower odds of hepatic steatosis (odds ratio 0.43, 95% CI 0.20-0.93) compared with women in the lowest tertile of sex hormone binding globulin (10.5-40.3 nmol/l). There was an interaction between race/ethnicity and medication use whereby non-Hispanic white women using medications had three times higher odds of hepatic steatosis compared with African-American women not using medications (odds ratio 3.36, 95% CI 1.07-10.58). Interactions between race/ethnicity and other variables, including sex hormone levels, were not significant. CONCLUSIONS: Hepatic steatosis on ultrasound may be more common in post-menopausal non-Hispanic white women than African-American women and was associated with lower levels of sex hormone binding globulin.

Recommendations from a multi-study evaluation of proposed criteria for staging reproductive aging.

In 2001, the Stages of Reproductive Aging Workshop (STRAW) proposed bleeding and endocrine criteria for defining the early and late menopausal transition stages. Based on expert consensus, STRAW recommended a shorter interval of amenorrhea than the commonly used 90-day amenorrhea criteria for late transition and a >7-day change in cycle length for early transition. The ReSTAGE collaboration used prospective menstrual calendar data from four cohorts (TREMIN, Melbourne Women's Midlife Health Project, Seattle Midlife Women's Health Study, and Study of Women's Health Across the Nation) to quantitatively evaluate STRAW's recommendations. This empirical assessment supported the STRAW recommendations that (1) > or =60 days of amenorrhea be used to define the late menopausal transition and (2) that early transition is consistent with a persistent 7 or more day difference in length of consecutive cycles. Serum follicle stimulating hormone (FSH) values > or =40 IU/l was an independent marker of the transition and, when occurring together with a bleeding marker, increased prediction of final menstrual period. Such a FSH criterion could be incorporated into the STRAW paradigm to facilitate prediction of proximity of the final menstrual period.

Birthweight-adjusted Dubowitz methods: reducing misclassification of assessments of gestational age in a Zimbabwean population.

OBJECTIVE: To evaluate the performance and the utility of using birthweight-adjusted scores of the Dubowitz method of estimating gestational age in a Zimbabwean population. DESIGN: A validation study. SETTING: Harare Maternity Hospital, from October to December 1999. SUBJECTS: 364 African newborn infants with a known last menstrual period (LMP), within the first 56 hours of life. MAIN OUTCOME MEASURES: Differences between regression lines and variances explained by Dubowitz scores obtained by examining newborn infants compared to gestational age calculated from the last menstrual period, in models with and without the addition of birthweight. RESULTS: The Dubowitz method was a good predictor of gestational age, useful in differentiating term from pre-term infants. The beta coefficients from regression lines with and without addition of birthweight differed significantly from each other (z = 2.83, p < 0.01). Our regression line without adding birthweight was Y(LMP gestational age) = 23.814 + 0.301* score. Addition of birthweight to the regression models improved prediction of gestational age, Y(LMP gestational age) = 23.512 + 0.219* score + 0.0015* grams, and accounted for 69% of the variance compared to 66% in models without birthweight. CONCLUSION: The introduction of birthweight improves estimation of gestational age, correcting for the overestimation reported for the original Dubowitz methods and the error caused by low birthweight. We recommend the use of our birthweight-adjusted Dubowitz maturity scales for studies of prematurity, and for routine clinical practice.

Natural history of bone loss over 6 years among premenopausal and early postmenopausal women.

The aims of this prospective cohort study were to determine rates of premenopausal and early postmenopausal bone loss, age at onset of bone loss, and whether rates of bone loss depend on baseline bone mineral density (BMD). The cohort of 614 women aged 24-44 years at baseline from the longitudinal Michigan Bone Health Study was followed for 6 years beginning in 1992-1993. Up to five BMD measurements of the lumbar spine (L(2-4)) and the femoral neck were obtained through 1998-1999 by using dual x-ray absorptiometry and were standardized (as z scores) relative to a young adult, female BMD distribution. Regression models were used to estimate rates of BMD change and to examine BMD as a function of age. At the lumbar spine, the rate of BMD change for premenopausal women varied with time. At the femoral neck, the rate of change was -1.6% (95% confidence interval: -0.9%, -2.3%) of a z score annually (annual loss of 0.3% of baseline BMD (g/cm(2))). Evidence for age at onset of bone loss at the lumbar spine was inconclusive. Bone loss began by the midtwenties at the femoral neck. Additional annual change of -0.7% (95% confidence interval: -0.2%, -1.2%) of a z score was observed at the femoral neck for each unit increase in BMD z score at baseline.

Improving the assessment of gestational age in a Zimbabwean population.

OBJECTIVES: To evaluate the performance and the utility of using birthweight-adjusted scores of Dubowitz and Ballard methods of estimating gestational age in a Zimbabwean population. METHOD: The Dubowitz and the Ballard methods of estimating gestational age were administered to 364 African newborn infants with a known last menstrual period (LMP) at Harare Maternity Hospital. RESULTS: Both methods were good predictors of gestational age useful in differentiating term from pre-term infants. Our regression line was Y((LMP gestational age))=23.814+0.301*score for the Dubowitz and Y((LMP gestational age))=24.493+0.420*score for the Ballard method. Addition of birthweight to the regression models improved prediction of gestational age; Y((LMP gestational age))=23.512+0.219*score+0.0015*grams for Dubowitz and Y((LMP gestational age))=24.002+0.292*score+0.0016*grams for Ballard method. CONCLUSIONS: We recommend the use of our birthweight-adjusted maturity scales; the Dubowitz for studies of prematurity, and the Ballard for routine clinical practice.

Factors associated with age at natural menopause in a multiethnic sample of midlife women.

An unprecedented number of women will experience menopause in the next decade. Although the timing of menopause affects long-term disease risk, little is known about factors that affect this timing. In the present 1995--1997 cross-sectional study, the Study of Women's Health Across the Nation, the relation of demographic and lifestyle factors to age at natural menopause was examined in seven US centers and five racial/ethnic groups. All characteristics were self-reported by women aged 40--55 years (n = 14,620). Cox proportional hazards models were used to estimate the probability of menopause by age. Overall, median age at natural menopause was 51.4 years, after adjustment for smoking, education, marital status, history of heart disease, parity, race/ethnicity, employment, and prior use of oral contraceptives. Current smoking, lower educational attainment, being separated/widowed/divorced, nonemployment, and history of heart disease were all independently associated with earlier natural menopause, while parity, prior use of oral contraceptives, and Japanese race/ethnicity were associated with later age at natural menopause. This sample is one of the largest and most diverse ever studied, and comprehensive statistical methods were used to assess factors associated with age at natural menopause. Thus, this study provides important insights into this determinant of long-term disease risk in women.

Risk factors for pre-eclampsia/eclampsia among working women in Mexico City.

This study examined risk factors for pre-eclampsia/eclampsia in a population-based sample of pregnant working women in Mexico City. Over a 3-month period, all women who gave birth at three major hospitals and who had worked for at least 3 months during pregnancy were interviewed. After excluding mothers with multiple gestations or infants with birth defects, and previous diagnoses of hypertension, chronic renal disease or diabetes, 131 of 2,436 women (5.4%) had been diagnosed with pre-eclampsia and/or eclampsia. The frequency was much higher among women of low socio-economic status: 12% of uninsured women (SSA) compared with 4.2% of private sector employees (IMSS) and 1.3% of public sector employees (ISSSTE). After adjusting for education, women working in services (OR = 1.68, 95% CI = 1.01, 2.81) and in retail (OR = 1.99, 95% CI = 1.18, 3.37), primiparae (OR = 2.64, 95% CI = 1.65, 4.21) and women whose pregestational weight was > or = 55 kg (OR = 2.02, 95% CI = 1.34, 3.04) were at increased risk. Efforts to develop and evaluate intervention programmes should target hospitals serving the uninsured (SSA) if reduction in the number of preventable maternal deaths in Mexico is to be achieved. Such programmes should also target service and retail workers and identify women with poor glycaemic control early in pregnancy.

Self-defined menopausal status in a multi-ethnic sample of midlife women.

OBJECTIVES: This study aimed to identify factors associated with women's perceived menopausal status and to evaluate agreement between women's self-designation and a menstrually-based classification in a multi-ethnic sample of women. METHODS: A cross-sectional survey was conducted as part of a large, seven-site, multi-ethnic study, the Study of Women's Health Across the Nation (SWAN). All variables were assessed by self-report in 13952 women aged 40-55 years. Multiple linear regression was used to assess determinants of self-defined menopausal status, stratifying by race/ethnicity within three anatomical/hormone use strata. Kappa statistics were used to evaluate agreement between the self-defined and menstrually-based classifications. RESULTS: For women with an intact uterus, at least one ovary and not using hormones, menstrual patterns explained about half the variance in self-defined menopause status with older women classifying themselves later in the transition. Disagreement between menstrually-based and self-defined menopausal status was 39, 38, 36, 32 and 29% for Hispanic, African-American, Japanese, Caucasian, and Chinese women, respectively (kappa statistics=0.46, 0.41, 0.40, 0.53 and 0.58). Women with vasomotor symptoms tended to self-designate themselves as being in transition regardless of their menstrual patterns. Age and 12 months of amenorrhea explained about 40% of the variance in self-categorization among women using hormones with an intact uterus. Bilateral oophorectomy, age and time since surgery explained about 20% of the variance among post-surgical women. CONCLUSIONS: Menstrual characteristics are strong predictors of women's self-perceived menopausal status. However, additional factors, including symptoms and cultural differences in the meaning of specific bleeding patterns, are also relevant and require further investigation.

Analysis of menstrual diary data across the reproductive life span applicability of the bipartite model approach and the importance of within-woman variance.

The nature of variability in menstrual function has not been adequately described or quantified across the reproductive life span. This article evaluates the applicability of the bipartite model approach to the analysis of menstrual data and the relative importance of within-woman variability across the reproductive life span using data from the Tremin Trust data, a large prospective study in which women maintained menstrual diaries throughout their reproductive life. We first consider how the boundaries of the Gaussian portion of the distribution change with age, and reflect upon the implications of these distribution changes for definitions of normal cycling. We next estimate the change in mean cycle length, in between- and within-woman variance and in the probability of having a nonstandard cycle across the reproductive life span. Finally, we characterize the dynamics of menstrual cycling within women over time at various points in the reproductive life span.

Effect of HIV infection on menstrual cycle length.

HIV serostatus and menstrual function were examined using prospectively collected menstrual data from 802 HIV-seropositive and 273 HIV-seronegative women, ages 20 to 44, enrolled in two cohort studies of HIV infection in North American women. The associations between HIV serostatus and the probabilities of having a cycle lasting >40 days (n = 541 cycles), >90 days (n = 67 cycles), <18 days (n = 316 cycles) and mean length and variability of 18 to 40 day cycles (n = 3,634) were assessed. After adjustment for demographic characteristics, body mass index, and substance use, seropositivity increased the odds of having a very short cycle (< 18 days, odds ratio [OR], 1.45; 95% confidence interval [CI], 1.00-2.11) and a very long cycle (>90 days, OR, 1.32; 95% CI, 0.68-2.58) slightly, although the latter CIs include one. Seropositivity did not increase the odds of having a moderately long cycle (>40 days, OR, 1.14) or affect mean cycle length or variability (beta, 0.30 +/- 0.20; between-woman standard deviation [SD], 2.2 days [HIV-seronegative] and 1.9 days [HIV-seropositive]; within-woman SD, 3.5 days for both). Although seropositivity may slightly increase the probability of very short cycles, HIV serostatus has little overall effect on amenorrhea, menstrual cycle length, or variability. Among HIV-seropositive women, higher viral loads and lower CD4+ counts were associated with increased cycle variability and polymenorrhea.

Menstrual dysfunction: a missed opportunity for improving reproductive health in developing countries.

The field of population has undergone a paradigm shift to a broader focus on reproductive health, which recognises women's self-perceived health needs. Investigations in various countries reveal that menstruation is a primary concern of women. Yet sparse attention has been paid to understanding or ameliorating women's menstrual complaints. We propose including the management of menstrual complaints as part of reproductive health programming. Next steps should include further quantitative and qualitative research to understand the prevalence, determinants and consequences of menstrual dysfunction; developing appropriate protocols and low-cost interventions for diagnosis and treatment of menstrual morbidity and training of health care workers in resource-scarce settings; and developing educational interventions to facilitate women's understanding of normal menstrual function and variability as well as of the types, causes and appropriate treatments for menstrual dysfunction.

Urinary oestrogen patterns in long follicular phases.

Long menstrual cycles have been associated with reduced risk of breast cancer and increased risk of osteoporosis. These observations have led to assumptions about the endogenous oestrogen exposure of women with long cycles. However, daily oestrogen profiles in long menstrual cycles have not been described. This paper examines daily urinary oestrogen profiles during the follicular phases of 416 conception and non-conception cycles. Women were aged 21-42 years, had no history of infertility and were not under treatment. Twenty-eight cycles were defined as long, with a follicular phase that lasted 24 days or more. Five patterns were observed among these long cycles, the most common being a pattern consistent with delayed emergence of a dominant follicle. Other patterns were a pattern consistent with demise and replacement of a dominant follicle, one consistent with delayed follicular recruitment, one showing a prolonged initial drop in oestrogen and one with an extended oestrogen peak. Average follicular phase oestrogen concentrations were highest in cycles with short follicular phases (7-11 days). Oestrogen concentrations from long follicular phases (24-59 days) did not differ substantially from follicular phases of usual length (12-17 days). The oestrogen profiles in long follicular phases are heterogeneous and not necessarily hypo-oestrogenic.