Postpartum depression and traditional postpartum care in China: role of zuoyuezi

OBJECTIVE

To determine the relationship between the traditional Chinese practice of postpartum care, known as zuoyuezi, and postpartum depression (PPD) in China.

METHODS

A total of 342 Chinese women were surveyed 6- to 8-weeks post partum using the Edinburgh Postnatal Depression Scale (EPDS) and items assessing sociodemographics, health history, peripartum experiences, zuoyuezi, and social support.

RESULTS

Prevalence of PPD was 15.5% (EPDS cutoff >or=13). PPD was associated with lower income, difficult pregnancy experience, poor infant health status, not attending childbirth classes, and low spousal involvement before and after delivery. Among the 96% of women who practiced zuoyuezi, those for whom the caregiver was her mother-in-law or who perceived zuoyuezi as unhelpful had twice the odds of PPD.

CONCLUSION

These data highlight the importance of the peripartum experience in assessing PPD risk. Zuoyuezi is still commonly practiced in urban China, and further research is needed to explore its role in the potential prevention of PPD.

Estradiol rates of change in relation to the final menstrual period in a population-based cohort of women

CONTEXT/OBJECTIVE

The aim was to characterize rates of change in serum estradiol (E2) levels across the menopausal transition and into early postmenopause.

SETTING/PARTICIPANTS

We studied the Michigan Bone Health and Metabolism Study cohort of 629 women with median age of 38 yr (interquartile range, 7) at the 1992-1993 baseline with annual assessment of E2 levels over the subsequent 15-yr period. DESIGN/MAIN OUTCOME MEASURES: The purpose was to describe patterns of acceleration/deceleration in (log)E2 rates of change before and after the final menstrual period (FMP) using nonparametric and piecewise regression modeling.

RESULTS

Between -10 to -2 yr to the FMP, mean fitted serum E2 population values were relatively stable. The 95% confidence bands around the slight increase in E2 rate of change 5 yr prior to the FMP included the value of no change. The fitted population mean E2 value declined 67% from 64.5 pg/ml (se = 3.6) to 21 pg/ml (se = 1.2) in the 4 yr between -2 < FMP < +2. A second significant mean E2 rate of change was identified from 6-8 yr after FMP. Fitted population mean E2 values declined 18% from 18.1 pg/ml (se = 1.3) at FMP = 6 to 14.8 pg/ml (se = 1.3) at FMP = 8. In nonobese women, the mean E2 percent decline was 42% from FMP = 6 to FMP = 8, whereas in obese women, the mean E2 percent decline over this time was 31%.

CONCLUSIONS

Population mean serum E2 levels were sustained until approximately 2 yr prior to the FMP. In the ensuing 4-yr period, E2 levels declined 67%. A secondary E2 decline, commencing about 6 yr after the FMP, was observed in nonobese but not obese women.

A hot-deck multiple imputation procedure for gaps in longitudinal data on recurrent events

We consider the analysis of longitudinal data sets that include times of recurrent events, where interest lies in variables that are functions of the number of events and the time intervals between events for each individual, and where some cases have gaps when the information was not recorded. Discarding cases with gaps results in a loss of the recorded information in those cases. Other strategies such as simply splicing together the intervals before and after the gap potentially lead to bias. A relatively simple imputation approach is developed that bases the number and times of events within the gap on matches to completely recorded histories. Multiple imputation is used to propagate imputation uncertainty. The procedure is developed here for menstrual calendar data, where the recurrent events are menstrual bleeds recorded longitudinally over time. The recording is somewhat onerous, leading to gaps in the calendar data. The procedure is applied to two important data sets for assessing the menopausal transition, the Melbourne Women's Midlife Health Project and the TREMIN data. A simulation study is presented to assess the statistical properties of the proposed procedure. Some possible extensions of the approach are also considered.

The ReSTAGE Collaboration: defining optimal bleeding criteria for onset of early menopausal transition

OBJECTIVE

Criteria for staging the menopausal transition are not established. This article evaluates five bleeding criteria for defining early transition and provides empirically based guidance regarding optimal criteria.

DESIGN/SETTING

Prospective menstrual calendar data from four population-based cohorts: TREMIN, Melbourne Women's Midlife Health Project (MWMHP), Seattle Midlife Women's Health Study (SMWHS), and Study of Women's Health Across the Nation (SWAN) with annual serum FSH from MWMHP and SWAN.

PARTICIPANTS

735 TREMIN, 279 SMWHS, 216 MWMHP, and 2270 SWAN women aged 35-57 at baseline who maintained menstrual calendars.

MAIN OUTCOME MEASURE(S)

Age at and time to menopause for: standard deviation >6 and >8 days, persistent difference in consecutive segments >6 days, irregularity, and >or=45 day segment. Serum FSH concentration.

RESULT(S)

Most women experienced each of the bleeding criteria. Except for a persistent >6 day difference that occurs earlier, the criteria occur at a similar age and at approximately the same age as late transition in a large proportion of women. FSH was associated with all proposed markers.

CONCLUSION(S)

The early transition may be best described by ovarian activity consistent with the persistent >6 day difference, but further study is needed, as other proposed criterion are consistent with later menstrual changes.

Helping midlife women predict the onset of the final menses: SWAN, the Study of Women's Health Across the Nation

OBJECTIVE

Women approaching menopause often ask their doctors, "When are my periods going to end?" The objective of this study was to predict time to the final menstrual period (FMP).

DESIGN

This multiethnic, observational cohort study, the Study of Women's Health Across the Nation, has been ongoing since 1996. Data collected from seven annual study visits were used. The community-based cohort from seven national sites included 3,302 white, African American, Hispanic, Chinese, and Japanese women aged 42 to 52 years at baseline with a uterus and at least one ovary, who were not pregnant or taking reproductive hormones, and had at least one menstrual period within the past 3 months at baseline. The time to the FMP was defined retrospectively after 12 months of amenorrhea. Uni- and multivariable Cox proportional hazard models, hazard ratios (HRs), and 95% CIs were computed for variables of interest.

RESULTS

A total of 2,662 women, of whom 706 had an observed FMP, were included. Age, menstrual cycles that had become farther apart (HR = 2.56, 95% CI = 1.94-3.39) or more variable (HR = 1.79, 95% CI = 1.45-2.21), and current smoking (HR = 1.68, 95% CI = 1.35-2.08) were all associated with shorter time to the FMP. Higher (log) follicle-stimulating hormone (HR = 2.32, 95% CI = 2.02-2.67) was related to a shorter time to the FMP, but the highest estradiol category (>or=100 pg/mL [367 pmol/L]) was associated with an earlier onset of the FMP (HR = 2.16, 95% CI = 1.63-2.89). The number of vasomotor symptoms was related to an earlier FMP, whereas higher physical activity and educational levels were associated with a later FMP.

CONCLUSIONS

Age, menstrual cycle recall, smoking status, and hormone measurements can be used to estimate when the FMP will occur, allowing for more precise estimates for older midlife women: in the most extreme cases, ie, age 54, high estradiol level, current smoking, and high follicle-stimulating hormone level, the FMP can be estimated to within 1 year.

Diet and Lifestyle Factors Associated with Premenstrual Symptoms in a Racially Diverse Community Sample: Study of Women's Health Across the Nation (SWAN)

AIMS

We sought to determine if the frequency of reported physical or emotional premenstrual symptoms (PMSx) was associated with (1) dietary intake of phytoestrogens, fiber, fat, or calcium, (2) consumption of alcohol or caffeine, (3) active or passive smoke exposure or lack of physical exercise, and (4) race/ethnicity or socioeconomic status.

METHODS

A cross-sectional analysis was conducted of PMSx and demographic and lifestyle factors reported at baseline in the multiethnic sample of 3302 midlife women in the Study of Women's Health Across the Nation (SWAN). Stepwise multiple logistic regression analyses were performed for the overall sample and for each racial/ethnic group for each of five PMSx groupings.

RESULTS

Most dietary factors were not related to PMSx. Fat intake was negatively associated with craving and bloating (adjusted odds ratio [AOR] = 0.56, p = 0.024), and fiber intake was positively associated with breast pain (AOR = 1.39, p = 0.037). Alcohol intake was negatively associated with anxiety and mood changes (AOR = 0.63, p = 0.045) and headaches (AOR = 0.50, p = 0.009). Current smoking (AOR = 1.60, p = 0.028) and passive smoke exposure (AOR = 1.56, p = 0.050) were positively associated with cramps and back pain. Symptom reporting differed significantly by race/ethnicity. PMSx were also associated with comorbidities, early perimenopausal status, depressive symptoms, and symptom sensitivity.

CONCLUSION

We found little evidence to support a role for diet in PMSx reporting. However, alcohol intake was positively associated with premenstrual anxiety and mood changes, and active and passive smoke exposure was associated with a number of PMSx. Ethnic differences in symptom reporting and associations of comorbidities, early perimenopausal status, depressive symptoms, and symptom sensitivity with reported PMSx were also observed.

Neurobehavioral development in children with potential exposure to pesticides

BACKGROUND

Children may be at higher risk than adults from pesticide exposure, due to their rapidly developing physiology, unique behavioral patterns, and interactions with the physical environment. This preliminary study conducted in Ecuador examines the association between household and environmental risk factors for pesticide exposure and neurobehavioral development.

METHODS

We collected data over 6 months in the rural highland region of Cayambe, Ecuador (2003-2004). Children age 24-61 months residing in 3 communities were assessed with the Ages and Stages Questionnaire and the Visual Motor Integration Test. We gathered information on maternal health and work characteristics, the home and community environment, and child characteristics. Growth measurements and a hemoglobin finger-prick blood test were obtained. Multiple linear regression analyses were conducted.

RESULTS

Current maternal employment in the flower industry was associated with better developmental scores. Longer hours playing outdoors were associated with lower gross and fine motor and problem solving skills. Children who played with irrigation water scored lower on fine motor skills (8% decrease; 95% confidence interval = -9.31 to -0.53), problem-solving skills (7% decrease; -8.40 to -0.39), and Visual Motor Integration test scores (3% decrease; -12.00 to 1.08).

CONCLUSIONS

These results suggest that certain environmental risk factors for exposure to pesticides may affect child development, with contact with irrigation water of particular concern. However, the relationships between these risk factors and social characteristics are complex, as corporate agriculture may increase risk through pesticide exposure and environmental contamination, while indirectly promoting healthy development by providing health care, relatively higher salaries, and daycare options.

Sociodemographic and nutritional correlates of neurobehavioral development: a study of young children in a rural region of Ecuador

OBJECTIVE

To identify and describe the sociodemographic and nutritional characteristics associated with neurobehavioral development among young children living in three communities in the northeastern Andean region of Cayambe-Tabacundo, Ecuador.

METHODS

Women in the study communities who had a child 3 to 61 months of age completed a questionnaire about maternal and child health and sociodemographic characteristics. The Ages and Stages Questionnaire (ASQ) was directly administered to 283 children by two trained interviewers. Growth measurements and a hemoglobin finger-prick blood test were obtained in 2003-2004. Prevalence of developmental delay was calculated, and associations between child development and maternal, child, and household characteristics were explored.

RESULTS

High frequencies of developmental delay were observed. Children 3 to 23 months old displayed delay in gross motor skills (30.1%), and children 48 to 61 months old displayed delay in problem-solving skills (73.4%) and fine motor skills (28.1%). A high frequency of both anemia (60.4%) and stunting (53.4%) was observed for all age groups. Maternal educational level was positively associated with communication and problem-solving skills, and monthly household income was positively associated with communication, gross motor, and problem-solving skills.

CONCLUSIONS

The results suggest a high prevalence of developmental delay and poor child health in this population. Child health status and the child's environment may contribute to developmental delay in this region of Ecuador, but sociodemographic factors affecting opportunities for stimulation may also play a role. Research is needed to identify what is causing high percentages of neurobehavioral developmental delay in this region of Ecuador.

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.

Characterizing daily urinary hormone profiles for women at midlife using functional data analysis

The availability of daily hormone values for entire menstrual cycles offers an opportunity to apply new analytic techniques that confirm current knowledge and provide new insights into patterns of changing hormone profiles in women as they transition to the menopause. The Study of Women's Health Across the Nation (SWAN) collected urine samples during 1997-1999 from one menstrual cycle or up to 50 days from 848 women who live in seven cities across the United States. These samples were assayed for the urinary forms of estrogen, progesterone, follicle-stimulating hormone, and luteinizing hormone. The authors used functional data analysis to study variability in the hormone patterns of 572 of the 848 pre- and early-perimenopausal women with evidence of a luteal transition. Functional data analysis enabled the authors to identify asymmetries in women's hormone patterns related to cycle length that are not captured with single hormone value comparisons. Longer cycles were characterized by increasing dyssynchrony between follicle-stimulating hormone and luteinizing hormone in the luteal phase.

Comparison of SWAN and WISE menopausal status classification algorithms

BACKGROUND

Classification of menopausal status is important for epidemiological and clinical studies as well as for clinicians treating midlife women. Most epidemiological studies, including the Study of Women's Health Across the Nation (SWAN), classify women based on self-reported bleeding history.

METHODS

The Women's Ischemia Syndrome Evaluation (WISE) study developed an algorithm using menstrual and reproductive history and serum hormone levels to reproduce the menopausal status classifications assigned by the WISE hormone committee. We applied that algorithm to women participating in SWAN and examined characteristics of women with concordant and discordant SWAN and WISE classifications.

RESULTS

Of the 3215 SWAN women with complete information at baseline (1995-1997), 2466 (76.7%) received concordant classifications (kappa = 0.52); at the fifth annual follow-up visit, of the 1623 women with complete information, 1154 (72.7%) received concordant classifications (kappa = 0.57). At each time point, we identified subgroups of women with discordant SWAN and WISE classifications. These subgroups, ordered by chronological age, showed increasing trends for menopausal symptoms and follicle-stimulating hormone (FSH) and a decreasing trend for estrogen (p < 0.001).

CONCLUSIONS

The WISE algorithm is a useful tool for studies that have access to blood samples for hormone data unrelated to menstrual cycle phase, with or without an intact uterus, and no resources for adjudication. Future studies may want to combine aspects of the SWAN and WISE algorithms by adding hormonal measures to the series of bleeding questions in order to determine more precisely where women are in the perimenopausal continuum.

Factors associated with prevalent and incident urinary incontinence in a cohort of midlife women: a longitudinal analysis of data: study of women's health across the nation

To compare the characteristics of and baseline factors associated with prevalent and incident urinary incontinence in a diverse cohort of midlife women, the authors analyzed the baseline and first five annual follow-up visits of the Study of Women's Health Across the Nation (SWAN), 1995-2001. From responses to annual questionnaires, the authors defined prevalent incontinence as at least monthly incontinence reported at baseline and incident incontinence as at least monthly incontinence first reported over follow-up. They used multiple logistic regression for their comparison. The mean age of their cohort at baseline was 45.8 (standard deviation: 2.7) years. Prevalent incontinence was 46.7%, and the average incidence was 11.1% per year. Most women reported stress, but a higher proportion developed urge incontinence (15.9% vs. 7.6% at baseline). African Americans (29.5%) and Hispanics (27.5%) had the lowest prevalence of incontinence; African Americans (11.6%) and Caucasians (13.4%) had the highest average annual incidence. Parity, diabetes, fibroids, and poor social support were associated with prevalent incontinence, while high body mass index, high symptom sensitivity, and poor health were associated with incident incontinence. In midlife women, incident incontinence is mild with different characteristics and baseline risk factors; overweight women have a higher risk of developing incontinence.

Effect of community of residence on neurobehavioral development in infants and young children in a flower-growing region of Ecuador

OBJECTIVE

In this study we compared neurobehavioral development in Ecuadoran children living in two communities with high potential for exposure to organophosphate (OP) and carbamate pesticides to that of children living in a community with low potential for exposure.

METHODS

Women residing in the study communities who had a child 3-61 months of age completed a questionnaire about maternal and child health and sociodemographic characteristics. The Ages and Stages Questionnaire (ASQ) was administered to each child (n = 283). Growth measurements and a hemoglobin finger-prick blood test were obtained. We used multiple linear regressions to evaluate associations between community of residence and delayed development, adjusting for child health status and other characteristics of the home environment.

RESULTS

Children 3-23 months of age who resided in high-exposure communities scored lower on gross motor (p = 0.002), fine motor (p = 0.06), and socioindividual (p-value = 0.02) skills, compared with children in the low-exposure community. The effect of residence in a high-exposure community on gross motor skill development was greater for stunted children compared with non-stunted children (p = < 0.001) in the same age group of 3-23 months. Children 24-61 months of age residing in the high-exposure communities scored significantly lower on gross motor skills compared with children of similar ages residing in the low-exposure community (p = 0.06).

CONCLUSIONS

Residence in communities with high potential for exposure to OP and carbamate pesticides was associated with poorer neurobehavioral development of the child even after controlling for major determinants of delayed development. Malnourished populations may be particularly vulnerable to neurobehavioral effects of pesticide exposure.

Reliability and Validity of Self-Reported Symptoms for Predicting Vulvodynia

OBJECTIVE

To evaluate the reliability and validity of self-reported symptoms to predict vulvodynia, compared with examination-based confirmation.

METHODS

Between August 5, 2004, and December 13, 2004, 1,046 members of the University of Michigan Women's Health Registry were surveyed regarding the presence of symptoms suggestive of vulvodynia. Diagnoses of vulvodynia and of control status based on survey responses were made, and a subset of these respondents was evaluated in the office.

RESULTS

One thousand forty-six of 1,447 (72.3%) eligible women, aged 19 to 92 years, completed the survey. Seventy-nine (7.6%) of the survey respondents who reported ongoing vulvar pain lasting more than 3 months were predicted to have vulvodynia, while women reporting no current pain with intercourse and no history of prolonged vulvar pain were predicted to be controls (N = 543). Agreement between the history taken at the office and that reported on the survey was very good (reliability: Cohen's kappa = 0.86, 95% confidence interval 0.73-0.99). Of the 28 women predicted to have vulvodynia who were examined in the office, 27 (96.4%) were confirmed to have vulvodynia, and 28 of the 34 (82.4%) asymptomatic women examined did not have increased vulvar sensitivity (Cohen's kappa = 0.78, 95% confidence interval 0.64-0.92).

CONCLUSION

Excellent reliability and validity of survey responses for predicting vulvodynia were demonstrated.

LEVEL OF EVIDENCE

II-2.

Evaluation of four proposed bleeding criteria for the onset of late menopausal transition

CONTEXT

The current criterion for onset of late menopausal transition is amenorrhea of 90 d or more. The Stages of Reproductive Aging Workshop proposed alternative criteria based on a shorter period of amenorrhea. Empirical data comparing proposed criteria are not available.

OBJECTIVE

This paper evaluates the several bleeding criteria that served as the basis of these recommendations. The goal was to provide empirically based guidance regarding which bleeding criterion may be optimal for widespread application in clinical and research settings.

DESIGN/SETTING

The study used prospective menstrual calendar data from four community and population-based cohort studies: TREMIN, Melbourne Women's Midlife Health Project, Seattle Midlife Women's Health Study, and Study of Women's Health Across the Nation.

PARTICIPANTS

The study included 735 TREMIN, 279 Seattle Midlife Women's Health Study, 216 Melbourne Women's Midlife Health Project, and 2270 Study of Women's Health Across the Nation women aged 35-57 yr at baseline who contributed 10 menstrual cycles or more.

MAIN OUTCOME MEASURE(S)

The main measures were the frequency of and median age at occurrence and time from occurrence to final menstrual period (FMP) for four criteria: skipped segment, 10-segment running range, 60- and 90-d amenorrhea.

RESULTS

A skipped segment, 10-segment running range greater than 42 d and 60-d amenorrhea identify a similar time in women's reproductive lives. The latter two identify the exact same date in two thirds of women. All three criteria occur in a greater proportion of women than the 90-d criterion and are equally predictive of the FMP, although they occur 1-2 yr earlier.

CONCLUSIONS

These findings support the recommendation of the Stages of Reproductive Aging Workshop that 60 d of amenorrhea be used to define onset of the late menopausal transition.

The value of follicle-stimulating hormone concentration and clinical findings as markers of the late menopausal transition

CONTEXT

The Stages of Reproductive Aging Workshop proposed bleeding and hormonal criteria for the menopausal transition, but operational definitions of hormone parameters were not specified.

OBJECTIVE

This paper investigates the longitudinal relationship of annual serum FSH levels with four proposed bleeding criteria for the late menopausal transition in two cohort studies. The goal is to provide empirically based guidance regarding application of hormonal criteria that may be optimal for widespread application in clinical and research settings for assessing menopausal stage.

DESIGN/SETTING

Prospective menstrual calendar and annual serum FSH data were collected from two population-based cohort studies: the Melbourne Women's Midlife Health Project and the Study of Women's Health Across the Nation.

PARTICIPANTS

Participants in the study were 193 Melbourne Women's Midlife Health Project and 2223 Study of Women's Health Across the Nation women aged 42-57 yr at baseline who contributed 10 or more menstrual cycles and at least one annual serum FSH value.

MAIN OUTCOME MEASURE(S)

Association between bleeding criteria for the late menopausal transition and FSH was a main outcome measure. Associations of bleeding criteria, FSH, and hot flashes with the final menstrual period were also measured.

RESULTS

A single FSH measure is an independent marker of the late menopausal transition, but FSH concentrations are less predictive of menopausal stage than any of four proposed bleeding criteria. Criterion FSH values for the late transition are similar across both studies. Experience of hot flashes adds no information in the presence of hormonal and bleeding criteria.

CONCLUSIONS

An annual serum FSH concentration of 40 IU/liter could be incorporated, in conjunction with bleeding markers, into the Stages of Reproductive Aging Workshop paradigm for markers of the late menopausal transition.

Age at natural menopause and factors associated with menopause state among Puerto Rican women aged 40-59 years, living in Puerto Rico

OBJECTIVE

The timing of menopause is associated with multiple health outcomes in female populations including all-cause mortality, heart disease, breast cancer, and osteoporosis. Although research suggests that age at menopause varies in different ethnic groups, data on age at menopause among Hispanic women are limited.

DESIGN

The present cross-sectional study estimates age at natural menopause among a sample of 1,272 Puerto Rican women aged 40 to 59 years who participated in health fairs held in 22 municipalities of Puerto Rico between May 2000 and November 2001. Cox proportional hazard regression analysis was used to characterize age at natural menopause and its association with relevant covariates.

RESULTS

The overall adjusted median age at natural menopause was 51.3 years. Current employment (hazard ratio = 0.75, 95% CI: 0.59-0.95) and parity of two or three children as compared with having no children or one child (hazard ratio = 0.73, 95% CI: 0.54-0.98) were associated with a later menopause.

CONCLUSIONS

This study provides a robust estimate of age at menopause for Puerto Rican women, which is similar to overall estimates previously reported for US populations, but higher than estimates for other Hispanic populations. Our results confirm attributes associated with age at menopause and provide information relevant to understanding the potential chronic disease burden of Puerto Rican women as they age.

A varying-coefficient Cox model for the effect of age at a marker event on age at menopause

It is of recent interest in reproductive health research to investigate the validity of a marker event for the onset of menopausal transition and to estimate age at menopause using age at the marker event. We propose a varying-coefficient Cox model to investigate the association between age at a marker event, defined as a specific bleeding pattern change, and age at menopause, where both events are subject to censoring and their association varies with age at the marker event. Estimation proceeds using the regression spline method. The proposed method is applied to the Tremin Trust data to evaluate the association between age at onset of the 60-day menstrual cycle and age at menopause. The performance of the proposed method is evaluated using a simulation study.

Incidence of stillbirth and perinatal mortality and their associated factors among women delivering at Harare Maternity Hospital, Zimbabwe: a cross-sectional retrospective analysis

Background

Death of an infant in utero or at birth has always been a devastating experience for the mother and of concern in clinical practice. Infant mortality remains a challenge in the care of pregnant women worldwide, but particularly for developing countries and the need to understand contributory factors is crucial for addressing appropriate perinatal health.

Methods

Using information available in obstetric records for all deliveries (17,072 births) at Harare Maternity Hospital, Zimbabwe, we conducted a cross-sectional retrospective analysis of a one-year data, (1997–1998) to assess demographic and obstetric risk factors for stillbirth and early neonatal death. We estimated risk of stillbirth and early neonatal death for each potential risk factor.

Results

The annual frequency of stillbirth was 56 per 1,000 total births. Women delivering stillbirths and early neonatal deaths were less likely to receive prenatal care (adjusted relative risk [RR] = 2.54; 95% confidence intervals [CI] 2.19–2.94 and RR = 2.52; 95% CI 1.63–3.91), which for combined stillbirths and early neonatal deaths increased with increasing gestational age (Hazard Ratio [HR] = 3.98, HR = 7.49 at 28 and 40 weeks of gestation, respectively). Rural residence was associated with risk of infant dying in utero, (RR = 1.33; 95% CI 1.12–1.59), and the risk of death increased with increasing gestational age (HR = 1.04, HR = 1.69, at 28 and 40 weeks of gestation, respectively). Older maternal age was associated with risk of death (HR = 1.50; 95% CI 1.21–1.84). Stillbirths were less likely to be delivered by Cesarean section (RR = 0.64; 95% CI 0.51–0.79), but more likely to be delivered as breech (RR = 4.65; 95% CI 3.88–5.57, as were early neonatal deaths (RR = 3.38; 95% CI 1.64–6.96).

Conclusion

The frequency of stillbirth, especially macerated, is high, 27 per 1000 total births. Early prenatal care could help reduce perinatal death linking the woman to the health care system, increasing the probability that she would seek timely emergency care that would reduce the likelihood of death of her infant in utero. Improved quality of obstetric care during labor and delivery may help reduce the number of fresh stillbirths and early neonatal deaths.

Transactional sex among women in Soweto, South Africa: prevalence, risk factors and association with HIV infection

Sex workers have long been considered a high-risk group for HIV infection, but to date little quantitative research has explored the association between HIV risk and exchange of sex for material gain by women in the general population. The objective of this study was to estimate the prevalence of such transactional sex among women attending antenatal clinics in Soweto, South Africa, to identify demographic and social variables associated with reporting transactional sex, and to determine the association between transactional sex and HIV serostatus. We conducted a cross-sectional study of women seeking antenatal care in four Soweto health centres who accepted routine antenatal HIV testing. Private face-to-face interviews covered socio-demographics, sexual history and experience of gender-based violence. 21.1% of participants reported having ever had sex with a non-primary male partner in exchange for material goods or money. Women who reported past experience of violence by male intimate partners, problematic substance use, urban residence, ever earning money, or living in substandard housing were more likely to report transactional sex, while women who reported delayed first coitus, were married, or had a post-secondary education were less likely to report transactional sex. Transactional sex was associated with HIV seropositivity after controlling for lifetime number of male sex partners and length of time a woman had been sexually active (OR = 1.54, 95% CI: 1.07, 2.21). Women who reported non-primary partners without transactional sex did not have increased odds of being HIV seropositive (OR = 1.04, 95% CI: 0.75, 1.43). We conclude that transactional sex may place women at increased risk for HIV, and is associated with gender-based violence, substance use and socio-economic disadvantage. Research, policy and programmatic initiatives should consider the role of transactional sex in women's HIV risk, with attention to the intersecting roles of violence, poverty, and substance use in shaping women's sexual behaviour.

Risk factors for prematurity at Harare Maternity Hospital, Zimbabwe

BACKGROUND

Prematurity remains the main cause of mortality and morbidity in infants and a problem in the care of pregnant women world-wide. This preliminary study describes the socio-demographic, reproductive, medical, and obstetrical risk factors for having a live pre-term delivery (PTD) in Zimbabwe.

METHODS

This case-control study examined risk factors for PTD, at Harare Maternity Hospital between March and June 1999.

RESULTS

The frequency of PTD among live birth was 16.4%. Prior history of stillbirth or abortion was associated with PTD (adjusted relative risk [ARR] 1.50; 95% CI: 1.06, 2.11). Nutritional factors, including drinking a local non-alcoholic beverage (mahewu) during pregnancy and mother's increasing mid-arm circumference reduced the risk of PTD (ARR = 0.75; 95% CI: 0.60, 0.93 and ARR = 0.95; 95% CI: 0.92, 0.99 per cm of circumference, respectively). Obstetric conditions including eclampsia, anaemia, ante-partum haemorrhage, and placenta praevia were infrequent, but when present, were strongly associated with PTD (ARR = 3.57; 95% CI: 1.67, 7.63; ARR = 4.12; 95% CI: 1.80, 9.43; ARR = 3.05; 95% CI: 1.86, 5.00 and ARR = 3.30; 95% CI: 1.34, 8.14, respectively). Malaria, although less frequent, nonetheless was associated with an increased risk of PTD (ARR = 2.93; 95% CI: 1.70, 5.04). These results suggest that in addition to established obstetric risk factors, nutrition and malarial infection are important. About 43% of the mothers initiated prenatal care after 28 weeks of gestation.

CONCLUSION

Addressing prematurity in this population will require earlier initiation of prenatal care to allow for early detection and management of complications of pregnancy, and improving nutritional status of reproductive age with locally available foods. Further exploration of the potential benefits of mahewu, is warranted.

Prevalence and patterns of gender-based violence and revictimization among women attending antenatal clinics in Soweto, South Africa

Gender-based violence is a key health risk for women globally and in South Africa. The authors analyzed data from 1,395 interviews with women attending antenatal clinics in Soweto, South Africa, between November 2001 and April 2002 to estimate the prevalence of physical/sexual partner violence (55.5%), adult sexual assault by nonpartners (7.9%), child sexual assault (8.0%), and forced first intercourse (7.3%). Age at first experience of each type of violence was modeled by the Kaplan-Meier method, and Cox hazard models with time-varying covariates were used to explore whether child sexual assault and forced first intercourse were associated with risk of violent revictimization in adulthood. Child sexual assault was associated with increased risk of physical and/or sexual partner violence (risk ratio = 2.43, 95% confidence interval: 1.93, 3.06) and with adult sexual assault by a nonpartner (risk ratio = 2.33, 95% confidence interval: 1.40, 3.89). Forced first intercourse was associated with increased risk of physical and/or sexual partner violence (risk ratio = 2.64, 95% confidence interval: 2.07, 3.38) and nonsignificantly with adult sexual assault by a nonpartner (risk ratio = 2.14, 95% confidence interval: 0.92, 4.98). This study confirms the need for increased attention by the public health community to primary and secondary prevention of gender-based violence, with a specific need to reduce risk among South African adolescents.

Gender-based violence, relationship power, and risk of HIV infection in women attending antenatal clinics in South Africa

BACKGROUND

Gender-based violence and gender inequality are increasingly cited as important determinants of women's HIV risk; yet empirical research on possible connections remains limited. No study on women has yet assessed gender-based violence as a risk factor for HIV after adjustment for women's own high-risk behaviours, although these are known to be associated with experience of violence.

METHODS

We did a cross-sectional study of 1366 women presenting for antenatal care at four health centres in Soweto, South Africa, who accepted routine antenatal HIV testing. Private face-to-face interviews were done in local languages and included assessement of sociodemographic characteristics, experience of gender-based violence, the South African adaptation of the Sexual Relationship Power Scale (SRPS), and risk behaviours including multiple, concurrent, and casual male partners, and transactional sex.

FINDINGS

After adjustment for age and current relationship status and women's risk behaviour, intimate partner violence (odds ratio 1.48, 95% CI 1.15-1.89) and high levels of male control in a woman's current relationship as measured by the SRPS (1.52, 1.13-2.04) were associated with HIV seropositivity. Child sexual assault, forced first intercourse, and adult sexual assault by non-partners were not associated with HIV serostatus.

INTERPRETATION

Women with violent or controlling male partners are at increased risk of HIV infection. We postulate that abusive men are more likely to have HIV and impose risky sexual practices on partners. Research on connections between social constructions of masculinity, intimate partner violence, male dominance in relationships, and HIV risk behaviours in men, as well as effective interventions, are urgently needed.

Sampling strategies for prospective studies of menstrual function

Little information is available about optimal sampling strategies for prospective studies of menstrual function. Sample size and study duration for menstrual studies have often been driven as much by feasibility and cost as by statistical principles, with follow-up lasting 6 months to 2 years and sample size ranging from 100 to 500 women. Whether these studies are sufficiently powered to address common study objectives has not been adequately evaluated, and sample size estimates rarely account for the repeated nature of menstrual cycle data. Using data from the Tremin Trust (a study of menstrual function across the reproductive life span initiated in Minneapolis, Minnesota, in 1935 with data collected through 1977), the authors determined sampling strategies for assessing differences in mean cycle length between two exposure groups and for assessing change in mean cycle length across the reproductive life span. Following a larger number of women for 1-2 years is optimal for studies of host and environmental exposures that alter menstrual function. In contrast, following fewer women for an extended period of time, for example, 4-5 years, is optimal when studying how menstrual patterns vary across the reproductive life span in different populations.

Change in estradiol and follicle-stimulating hormone across the early menopausal transition: effects of ethnicity and age

Serum reproductive hormone concentrations were measured longitudinally in a community-based, multiethnic population of midlife women to assess whether ethnic differences exist in the patterns of change in estradiol (E2) and FSH and, if so, whether these differences are explained by host characteristics. We studied 3257 participants from seven clinical sites in the Study of Women's Health Across the Nation (SWAN) who were aged 42-52 yr at baseline and self-identified as African American (28.2%), Caucasian (47.1%), Chinese (7.7%), Hispanic (8.4%), or Japanese (8.6%). E2 and FSH were assayed in serum collected primarily in the early follicular phase of a spontaneous menstrual cycle in three consecutive annual visits. The primary explanatory variables included in repeated-measures regression analyses were race/ethnicity, menopausal status, age, body mass index (BMI), day of the cycle, smoking, parity, socioeconomic status, study site, and the self-report of diabetes at baseline. At the baseline visit, 46.2% of the women were classified as being early perimenopausal, with the remaining being premenopausal. By the second follow-up visit, 5.5% of the women in that cohort were postmenopausal, 66.8% were early perimenopausal, 8.3% were late perimenopausal, and 19.4% remained premenopausal. Serum E2 concentrations decreased significantly with age, with a steeper decline at higher ages. FSH concentrations increased significantly with age, with a steeper increase at higher ages. Similar patterns in the decline of E2 and the increase in FSH with age were found across ethnic groups, but the levels of these hormones differed by race/ethnicity. Specifically, over time, Chinese and Japanese women had lower E2 concentrations but similar FSH levels, compared with Caucasian women, and African American women had higher FSH concentrations but comparable E2 levels with those of Caucasian women. These ethnic differences in E2 and FSH were independent of menopausal status. The effect of BMI on serum E2 and FSH levels varied by menopausal status. Increasing BMI was associated with decreasing concentrations of E2 among premenopausal and early perimenopausal women but was associated with increasing concentrations of E2 among late perimenopausal and postmenopausal women. Increasing BMI was associated with decreasing concentrations of FSH, with the effect of BMI becoming larger as women transitioned through menopause. We conclude that serum E2 levels decrease and FSH concentrations increase with increasing age in midlife women, that ethnic differences in E2 over time differ from ethnic differences in FSH and suggest ethnic differences in the pituitary-ovarian relationship, and that the effect of BMI on E2 and FSH concentrations varies by menopausal status.

Science-based trade disputes: a new challenge in harmonizing the evidentiary systems of law and science

In November 2001, the University of Michigan hosted one of the first dialogues among international trade law scholars and scientists in the field of risk assessment with the goal of identifying critical areas of misunderstanding between the two fields. This article discusses key issues that need to be addressed in order to better harmonize the scientific and legal systems of evidence within the context of trade disputes and trade law and presents the recommendations that emerged from the Michigan meeting.

Incidence of and socio-demographic risk factors for stillbirth, preterm birth and low birthweight among Zimbabwean women

Data on birth outcomes are important for planning maternal and child health care services in developing countries. Only a few studies have examined frequency of birth outcomes in Zimbabwe, none of which has jointly examined the spectrum of poor birth outcomes across important demographic subgroups. We assessed delivery patterns and birth outcomes in 17 174 births over a one-year period from October 1997 to September 1998 at Harare Hospital, Zimbabwe. The annual rate of stillbirth was 61 per 1000 live births, rate of preterm birth (<37 weeks) was 168 per 1000, and low birthweight (LBW) (<2500 g) was 199 per 1000. Not attending antenatal care (prenatal care) was associated with increased risks of stillbirth [relative risk (RR) = 2.54, 95% CI 2.21, 2.92], preterm delivery [RR = 2.43, 95% CI 2.26, 2.61] and LBW births [RR = 2.16, 95% CI 2.02, 2.31]. Preterm births and LBW births were more likely to be stillborn [RR = 7.26, 95% CI 6.28, 8.39 and RR = 6.85, 95% CI 5.94, 7.91]. In conclusion, the rate of stillbirth is high and is predominantly associated with preterm births and to a lesser extent LBW. Reducing the frequency of stillbirth will require a better understanding of the determinants of preterm births and strategies for addressing this particular subset of high-risk births.

Staging reproductive aging: a comparison of proposed bleeding criteria for the menopausal transition

OBJECTIVE

A staging system for female reproductive aging has recently been proposed. Bleeding criteria are an important component of a staging system, as bleeding patterns are readily observable. Several different bleeding criteria have been proposed, but their concordance and validity have not been evaluated. Five proposed bleeding criteria or markers for the onset of early menopausal transition and four criteria for the onset of the late transition were evaluated using data from the Menstruation and Reproductive History Study, or Tremin Trust.

DESIGN

Correlations between time from age 35 to each marker event were assessed using Kendall's tau correlation coefficients. Kaplan-Meier survival analysis was used to examine associations between the marker events and age at final menstrual period (FMP).

RESULTS

The first occurrence of marker events for the late menopausal transition demonstrated low to high correlation (r = 0.23 to 0.77), whereas the first occurrence of marker events for the early transition stage demonstrated no correlation to moderate correlation (r = 0.0 to 0.65). After age 40, the occurrence of the marker events distinguished a subgroup of women who were more proximate to their FMP. Differences in years to FMP between women with and without the marker events were greatest in the early to mid-40s and declined with age.

CONCLUSIONS

A 60-day cycle may be a desirable marker for entry into the late transition stage because of its reliability, proximity to the FMP, and ease of calculation. More work is needed to conceptually define the onset of the early menopausal transition before appropriate bleeding criteria can be established.

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.

Substance use and psychotherapeutic medications: a likely contributor to menstrual disorders in women who are seropositive for human immunodeficiency virus

OBJECTIVE

The purpose of this study was to evaluate the impact of substance use and psychotherapeutic medications on menstrual characteristics in women who are human immunodeficiency virus seropositive and seronegative.

STUDY DESIGN

Menstrual calendars were prospectively collected for 1075 women who were human immunodeficiency virus seropositive and seronegative and who were enrolled in the Women's Interagency Human Immunodeficiency Virus Study or the Human Immunodeficiency Virus Epidemiology Research Study; several of the women were substance users or recipients of psychotherapeutic medications.

RESULTS

Women who received methadone maintenance and who used injection drugs had substantially increased odds of a cycle of >or=90 days (odds ratio, 2.28; 95% CI, 1.23-4.22; and odds ratio, 3.87; 95% CI, 2.16-6.95, respectively). The use of psychotherapeutic medications increased the odds of having very short cycles, <18 days, and cycles of >or=90 days (odds ratio, 1.69; 95% CI, 1.16-2.45; and odds ratio, 1.86; 95% CI, 1.03-3.36, respectively).

CONCLUSION

Clinicians should evaluate substance use, participation in methadone maintenance programs, and the use of psychotherapeutic medications and consider the neuroendocrinologic effects of these medications as a potential cause of menstrual disruptions.

Thyroid stimulating hormone (TSH) concentrations and menopausal status in women at the mid-life: SWAN

OBJECTIVE

We evaluated menopausal symptoms, menstrual cycle bleeding characteristics and reproductive hormones for their associations with thyroid stimulating hormone (TSH) concentrations in women at the mid-life from five ethnic groups.

METHODS

This report is from the baseline evaluation of the Study of Women's Health Across the Nation (SWAN), a community-based multiethnic study of the natural history of the menopausal transition. Enrollees were 42-52 years old (pre- and early perimenopausal) African American, Caucasian, Chinese, Hispanic and Japanese women (n = 3242). Enrollees were interviewed about self-reported diagnosed hypo- and hyperthyroidism or thyroid treatment, menopausal symptoms and menstrual cycle bleeding characteristics. Serum was assayed for TSH, oestradiol, testosterone, FSH and SHBG.

RESULTS

There were 6.2% of women with TSH > 5.0 mIU/ml and 3.2% with TSH < 0.5 IU/ml, cutpoints that have been used to encompass clinical and subclinical hypo- and hyperthyroidism, respectively. African American women had significantly lower mean TSH concentrations than Caucasian, Hispanic and Chinese women. Of the more than 15 menopause symptoms evaluated, only fearfulness was associated with having a TSH value > 5.0 mIU/ml (P < 0.008) or < 0.5 mIU/ml (P < 0.02). Women with TSH values outside the range of 0.5-5.0 mIU/ml were more likely to report shorter or longer menstrual periods (P = 0.004 for both) than women within that range. FSH, SHBG, dehydroepiandrosterone sulphate (DHEA-S), testosterone, and oestradiol concentrations were not associated with TSH concentrations.

CONCLUSION

In mid-aged women, there was a 9.6% prevalence of TSH values outside the euthyroid range of 0.5-5.0 mIU/ml. Although TSH was associated with bleeding length and self-reported fearfulness, it was not associated with indicators of the menopausal transition, including menopausal stage defined by bleeding regularity, menopausal symptoms or reproductive hormone concentrations.

Self-reported heavy bleeding associated with uterine leiomyomata

OBJECTIVE

To characterize the relationship between self-reported bleeding symptoms and uterine leiomyoma size and location.

METHODS

The leiomyoma status of a randomly selected sample of women aged 35-49 in the Washington, DC, area was determined using abdominal and transvaginal ultrasound to measure size and location of leiomyomata found at screening. Women were asked about symptoms of heavy bleeding (gushing-type bleeding, long menses, pad/tampon use) in a telephone interview. Using multivariable regression, we examined the relationships between leiomyoma characteristics and heavy bleeding symptoms among 910 premenopausal women.

RESULTS

Women with leiomyomata (n = 596) were more likely to report gushing-type bleeding than women without leiomyomata; risk increased with leiomyoma size. Adjusted relative risks with 95% confidence intervals (CI) for women in each leiomyoma size category compared with the reference category (women without leiomyomata) were as follows: adjusted relative risk of 1.4 (95% CI 1.1, 1.9) for diffuse only, adjusted relative risk of 1.4 (95% CI 1.1, 1.8) for small leiomyomata (less than 2 cm), adjusted relative risk of 1.6 (95% CI 1.3, 2.0) for medium leiomyomata (2-5 cm), and adjusted relative risk of 1.9 (95% CI 1.5, 2.5) for large leiomyomata (greater than 5 cm). Reported use of eight or more pads/tampons on the heaviest days of menstrual bleeding increased with leiomyoma size, with a nearly 2.5-fold risk for women with large leiomyomata compared with women without leiomyomata (adjusted relative risk of 2.4; 95% CI 1.8, 3.1). Nonsubmucosal leiomyomata were associated with essentially the same increase in heavy bleeding as submuscosal leiomyomata of similar size.

CONCLUSION

Small leiomyomata were associated with increased risk of heavy bleeding, and risk increased with size. Contrary to published articles, nonsubmucosal leiomyomata were associated with heavy bleeding to the same extent as submucosal leiomyomata.

Urinary incontinence predictors and life impact in ethnically diverse perimenopausal women

OBJECTIVE

To document prevalence of mild, moderate, and severe urinary incontinence among ethnically diverse perimenopausal women, identify risk factors, and assess the effect of severity on women's daily lives using treatment seeking, bother, and nighttime voiding as indicators.

METHODS

Baseline data from the longitudinal cohort of the Study of Women's Health Across the Nation, a prospective, multiethnic, multisite study of the natural history of menopausal transition was used (n = 3302). Interview and self-completed questionnaires assessed most variables of interest. Body mass index and diabetes mellitus were measured clinically. Incontinence severity was derived by multiplying frequency by volume leaked. Risk factors and effect on treatment seeking, bother, and nighttime voiding were assessed by the construction of multiple logistic regression models for each ethnic group and the total population.

RESULTS

Mean age was 46.4 years. Incontinence prevalence was 57%, with nearly 15% categorized as moderate and 10% as severe. Biologic factors constituted the most important risk for severity, specifically perimenopausal compared with premenepausal status (odds ratio [OR] 1.35), body mass index (OR 1.04), diabetes mellitus (OR 1.55), and current smoking (OR 1.38). Nonwhite groups had lower risk, but the relationship of ethnicity is complex. Severity was associated with likelihood of discussing with a health care provider, with bothersomeness, and with likelihood of nighttime voiding.

CONCLUSION

Large numbers of perimenopausal women experience urinary incontinence with 25% wearing protection or changing undergarments on several days per week. Mutable factors predicting severity included body mass index and current smoking.

Influence of medical conditions and lifestyle factors on the menstrual cycle

BACKGROUND

Few studies have described medical and lifestyle factors associated with various menstrual cycle characteristics.

METHODS

We analyzed cross-sectional data collected from 3941 premenopausal women from Iowa or North Carolina participating in the Agricultural Health Study between 1994 and 1996. Eligible women were age 21-40, not taking oral contraceptives, and not currently pregnant or breast feeding. We examined four menstrual cycle patterns: short cycles (24 days or less), long cycles (36 days or more), irregular cycles, and intermenstrual bleeding.

RESULTS

Long and irregular cycles were less common with advancing age and more common with menarche after age 14, with depression, and with increasing body mass index. The adjusted odds of long cycles increased with increasing body mass index, reaching 5.4 (95% confidence interval [CI] = 2.1-13.7) among women with body mass indexes of 35 or higher compared with the reference category (body mass index of 22-23). Smoking was associated with short cycles. Long cycles, irregular cycles, and intermenstrual bleeding were associated with a history of infertility. Having long cycles was associated with a doubling in the adjusted odds of having a fetal loss among women who had been pregnant within the last 5 years (odds ratio = 2.3; 95% CI = 0.9-5.7).

CONCLUSIONS

Menstrual patterns are influenced by a number of host and environmental characteristics. Factors that perturb menstruation may increase a woman's risk of other reproductive disorders.

Menstrual disorders in rural Gambia

As part of a community-based reproductive morbidity survey in rural Gambia, the prevalence and association of menstrual disorders with sociodemographic characteristics and other reproductive morbidities, and with knowledge, attitudes, and beliefs concerning menstrual problems were assessed. A questionnaire was administered by a field-worker and by a gynecologist, who also examined the women. Semistructured interviews were conducted to assess knowledge, attitudes, and beliefs in a subsample. Of 607 menstruating women not using hormonal contraceptives, 16 percent complained to the gynecologist of irregular cycles, 14 percent of dysmenorrhea, 8 percent of spotting, and 4 percent of heavy or prolonged bleeding. Each complaint was associated with other reproductive morbidities. A minority of women with menstrual problems had sought health care, and menstruation was revealed to be a highly personal and secretive topic in this population. Menstrual disorders constitute an important unaddressed area of reproductive health service needs in developing countries for which relatively simple and inexpensive therapies are often available. Information, education, and support combined with clinical management of menstrual problems should be core elements of reproductive health programs.

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.

DDT metabolite and androgens in African-American farmers

BACKGROUND

The ubiquitous dichlorodiphenyltrichloroethane (DDT) metabolite 1,1-dichloro-2,2-bis(p-chlorophenyl)ethylene (DDE) is an androgen receptor antagonist. Data on potential antiandrogenic activity of DDE in humans are limited.

METHODS

The relations between concentrations of plasma DDE and several serum androgens (total testosterone, bioavailable testosterone, 5alpha-dihydrotestosterone, and free androgen index) were examined in 137 North Carolina black male farmers, using multiple linear regression.

RESULTS

Participants ranged in age from 30 to 88 years (mean = 62 years). Most had farmed for about 30 years and 27% reported having used DDT. The median DDE level was 7.7 microg per liter (1213 microg per kg lipid), slightly higher than in other recent studies. Overall, concentrations of DDE and androgens were unrelated. Total testosterone decreased 2% (95% confidence limits [CL] = -9%, 5%) per increase in interquartile distance of lipid-adjusted DDE. The percentage change in other hormones was similarly negligible. However, among those whose DDE level was in the top tenth percentile, compared with all others, total testosterone and free androgen index were lower by 23% (CL= -40%, 1%) and 22% (CL =-41%, 4%) respectively. Plasma androgen levels decreased with age, a relation that has previously been studied only in whites.

CONCLUSIONS

Studies of more highly exposed populations may be needed to evaluate effects, if any, of DDE.

Pesticide use and pesticide-related symptoms among black farmers in the Agricultural Health Study

BACKGROUND

Health effects of pesticides have not been well studied in black farmers. We describe agricultural practices and pesticide-related symptoms in North Carolina black and white farmers participating in the Agricultural Health Study.

METHODS

Self-administered questionnaires were completed by 891 black and 11,909 white farmers licensed to apply restricted pesticides. Regression models were used to compare characteristics by race.

RESULTS

Black farmers reported lower lifetime pesticide use, less use of each class of pesticides (e.g., herbicides, insecticides), less use of high exposure application methods, and fewer pesticide-related symptoms such as headaches or dizziness, skin irritation, chest discomfort and feeling nervous or depressed than did white farmers.

CONCLUSIONS

Differences between black and white farmers may be explained by farm characteristics or economics. Despite lower use of pesticides, black farmers may have other work practices that affect exposure and risk.

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.