BACKGROUND: We hypothesize that premenopausal endogenous estradiol may be associated with age at menarche and adult overweight and obesity, potentially contributing to breast cancer risk. METHODS: We assessed age at menarche by questionnaire among 204 healthy Norwegian women, aged 25-35 years. Measures of body composition included body mass index (BMI, kg/m(2)), waist circumference (WC, cm), waist-to-hip ratio (WHR) and fat percentage dual energy X-ray absorptiometry, (DEXA). Daily salivary 17-beta-estradiol (E(2)) concentrations were collected throughout one entire menstrual cycle and assessed by radioimmunoassay (RIA). Linear regression analyses and linear mixed models for repeated measures were used and potential confounding factors and effect modifiers were tested. RESULTS: Among women with an early age at menarche (
OBJECTIVE: The human uterine cervix is capable of producing nitric oxide (NO). We studied the impact of cytological changes on the release of cervical NO. DESIGN: Population-based case-control study. SETTING: City of Helsinki, Finland. POPULATION: Cervical cytology tests and cervical fluid samples were collected in 297 women. METHODS: Cervical cytology tests, classified according to Bethesda criteria, were specifically analyzed for changes typically seen in human papillomavirus (HPV) infection, and the level of NO metabolites (NOx) in cervical fluid was assessed by Griess reaction. MAIN OUTCOME MEASURES: The difference in cervical fluid NOx between normal and abnormal cytology. RESULTS: Cervical cytology was normal in 219 women and abnormal in 78 women. Among women with abnormal cytology there was both a higher detection rate (89% vs. 71%) and a higher concentration of NOx (median 22.5 micromol/l, 95% CI 14.6-31.9 vs. 11.0 micromol/l, 95% CI 8.0-16.7) compared to women with normal cytology. Age, parity, use of oral contraceptives, phase of the menstrual cycle, or history of miscarriage or termination of early pregnancy were not linked to an increased cervical NOx level. CONCLUSIONS: Cervical cell changes (suggestive of HPV infection) are accompanied by an increased release of NO in the human cervix. The significance of this finding remains uncertain, but in theory, increased release of NO could modify the outcome of cervical infection.
A population-based case-control study was conducted in Sweden and Norway to analyse possible associations between breast cancer occurring before the age of 45 and several different characteristics of the women's reproductive life. A total of 422 (89.2%) of all eligible patients, and 527 (80.6%) of all eligible controls were interviewed. In univariate analyses, different characteristics of child-bearing (parity, age at first birth, years between last birth and diagnosis, duration of breast-feeding, and number of induced and spontaneous abortions), measures of the fertile or ovulating period (age at menarche, years between menarche and first pregnancy, and estimates of the menstruation span) and symptoms of anovulatory cycles or infertility were all seemingly unrelated to, or at most weakly associated with breast cancer. Adjustment for possible confounding factors in multivariate analyses resulted in largely unaltered risk estimates with odds ratios close to unity and without any significant trends when the exposure variables were studied in categorised or in continuous form. We conclude that reproductive factors did not explain the occurrence of breast cancer before the age of 45 in this population.
The aim of this study was to evaluate changes in the nitric oxide synthase inhibitor asymmetric dimethylarginine (ADMA) levels during different menstrual cycle phases in young adult women with or without oral contraceptive (OC) use.
The subjects (n=1079) originated from a large population-based, prospective cohort study conducted in Finland. Plasma ADMA, symmetric dimethylarginine (SDMA), L-arginine, C-reactive protein, creatinine, and brachial artery flow-mediated dilatation (FMD) were measured. The use of OCs and menstrual cycle phase were determined from a questionnaire.
In non-OC users, ADMA (P=0.017), L-arginine (P=0.002), and ADMA/SDMA ratio (P
During 1992-1995, 430 Danish couples were recruited after a nationwide mailing of a letter to 52,255 trade union members who were 20-35 years old, lived with a partner, and had no children. The couples were enrolled into the study when they discontinued birth control, and they were followed for six menstrual cycles or until a clinically recognized pregnancy. At enrollment and each month throughout the follow-up, both partners completed a questionnaire that asked them about their smoking, alcohol consumption, and intake of caffeinated beverages. The effect of current smoking and smoking exposure in utero was evaluated by using a logistic regression model with pregnancy outcome of each cycle in a Cox discrete model calculating the fecundability odds ratio. After adjustment for female body mass index and alcohol intake, diseases in female reproductive organs, semen quality, and duration of menstrual cycle, the fecundability odds ratio for smoking women exposed in utero was 0.53 (95% confidence interval (CI) 0.31-0.91) compared with unexposed nonsmokers. Fecundability odds ratio for nonsmoking women exposed in utero was 0.70 (95% CI 0.48-1.03) and that for female smokers not exposed in utero was 0.67 (95% CI 0.42-1.06). Exposure in utero was also associated with a decreased fecundability odds ratio in males (0.68, 95% CI 0.48-0.97), whereas present smoking did not reduce fecundability significantly. It seems advisable to encourage smoking cessation prior to the attempt to conceive as well as during pregnancy.
Despite warnings to abstain from alcohol, American women who are or could become pregnant still drink. This study evaluates whether women who consume alcohol are at an increased risk of recognizing pregnancy later than women who do not, adjusting for confounding factors that have been associated with alcohol consumption during pregnancy.
The sample included 863 control women from a multisite case-control study conducted from 1996 to 2002 in the United States and Canada. Telephone interviews were conducted with mothers by trained nurse interviewers who administered standardized questionnaires on demographic and reproductive factors, and pregnancy exposures.
Alcohol consumption was classified as none (42.0%), occasional (31.9%), regular (15.6%), and heavy (10.5%). Time to recognition of pregnancy was calculated as the date pregnancy was suspected minus the last menstrual period date (median: 31 days; range: 7-227 days). Unadjusted Cox proportional hazard models found that regular drinkers, but not heavy drinkers, had a significantly higher risk of recognizing pregnancy later than non-drinkers. However, this association went away after adjustment for demographic factors. Among women with unplanned pregnancies, heavy alcohol intake was associated with a 45% increased hazard ratio, compared to 0.80 for women with planned pregnancies; however, this finding was not statistically significant.
While time to pregnancy recognition did not vary among drinkers and non-drinkers, results from this study reiterate previous findings that pregnant women consume alcohol, and that drinkers share social and demographic characteristics that could be used to target public health interventions.
The authors studied the association between female and male alcohol intakes at the time of conception and the risk of spontaneous abortion, including early pregnancy loss detected by urinary human chorionic gonadotropin. After a nationwide mailing to about 50,000 members of four trade unions in Denmark in 1992-1994, 430 couples without previous pregnancy attempts were enrolled when birth control was discontinued, and they were followed until a clinically recognized pregnancy or for six menstrual cycles. Alcohol intake and potential confounding factors were reported in monthly questionnaires. Women collected morning urine for 10 days from the first day of vaginal bleeding in each cycle. The authors detected 186 pregnancies: 131 resulted in childbirth, and 55 resulted in spontaneous abortion (34 detected by urinary human chorionic gonadotropin). Depending on the intake in the cycle of conception and the adjustment factors, female alcohol intake was associated with 2-3 times the adjusted risk of spontaneous abortion compared with no intake, and male alcohol intake was associated with 2-5 times the adjusted risk. Only the adjusted relative risks for 10 or more drinks/week compared with no intake were statistically significant. Both male and female alcohol intakes during the week of conception increased the risk of early pregnancy loss.
Dietary exposure to persistent organochlorine compounds (POCs) has been found to affect the menstrual cycle in both animals and humans. In Sweden, the major exposure route for POCs is the consumption of fatty fish from the Baltic Sea. Thus, women who eat relatively large amounts of this fish constitute a suitable study group when investigating a possible association between dietary exposure to POC and menstrual cycle disruption. Questionnaires were sent to the exposed women, as well as to a socioeconomically similar cohort of controls, and information was collected on their menstrual cycles. Since the exposed women tended to smoke more than the controls, all results were adjusted for smoking habits. A cohort comparison found that the exposed women on average had 0.46 (95% confidence interval: 0.03, 0.89) days shorter menstrual cycles than controls. However, within the exposed cohort no effects were found of the proxy variables early life exposure and high consumption of Baltic Sea fatty fish. The results give some support to previous results from studies on women with similar exposure, but are not conclusive with respect to whether there is a causal association between POC exposure and menstrual cycle disruption.
The results of determination of the blood levels of dehydroepiandrosterone (DHEA) sulfate (DHEA-S) were comparatively assessed, by using the test systems "Steroid-IEA-DHEA-sulfate" (ZAO "Alkor Bio" (Saint Petersburg, Russia)) and "DHEA-S ELISA ("DRG Instruments GmbH (Germany)). The studies were conducted in apparently healthy 19-59-year-old women living in the middle belt of Western Siberia. They revealed the high sensitivity of the study test systems to age-related changes in the blood concentration of DHEA-S. The normal blood DHEA-S concentrations levels given in the instruction to the "DHEA-S ELISA" test systems were found to be decreased in they are used to measure the content of the above analyzed parameter in women aged 19-39 years.