Paternal occupational group and risk of offspring with neural tube defects

Selected paternal occupations as well as specific occupational exposures to chemicals such as organic solvents have been suggested as possible risk factors for neural tube defects (NTD). We investigated data from a population-based, case-control study of fetuses and liveborn infants with NTDs among 1989-91 California births and fetal deaths. Interviews were conducted with mothers of 538 NTD cases and 539 non- malformed controls. Mothers were asked to report the occupations that the fathers had in the period 3 months before and 3 months after conception. Each job title and industry reported was coded in accordance with the 1990 US Census. Considering those fathers who worked in managerial and professional occupations as the reference group, elevated odds ratios (OR) for NTDs were observed for the categories: technical, sales and administrative, OR = 1.5 [95% confidence interval 1.0, 2.4]; service, OR = 2.0 [1.2, 3.1]; farming, forestry and fishing, OR = 2.1 [1.3, 3.3]; operators, fabricators and labourers, OR = 1.8 [1.2, 2.7]; and military, OR = 1.9 [0.7, 5.0]. Stratification by NTD phenotype revealed that these elevated ORs were primarily observed for spina bifida phenotypes. Analyses adjusted for maternal body mass index, maternal periconceptional use of multivitamins containing folic acid, paternal race/ethnicity, maternal race/ethnicity and maternal education revealed attenuated risk estimates for most of the occupational groups. Analyses of 182 more specific occupational groups defined by aggregating fathers on similar job titles, when compared with fathers who worked in managerial and professional occupations, revealed that four job title groups were associated with fairly precise effect estimates of >or=1.5. These groups were: cooks; janitors and cleaners; farm workers; and groundsmen/gardeners. Using occupational titles as defined in previous investigations, we did not observe an elevated OR associated with paternal occupational solvent exposures, OR = 0.8 [0.5, 1.3]. These analyses generated potential clues regarding paternal occupational exposures as NTD risk factors. Risk variation observed by spina bifida phenotype is interesting and will need to be investigated further.     

Occupation and bladder cancer: a population-based,case-control study in Iowa

While considerable efforts have been made to investigate the role of occupation and industry in the risk of bladder cancer, many reported associations have not been consistent, and strong evidence of increased risk is apparent for few occupational groups. To further examine the issue, a large, population-based, case-control study was conducted in the state of Iowa among both men and women. A total of 1452 incident bladder cancer cases and 2434 controls were included in the study. Occupational history was collected from respondents for each job held for 5 years or longer since age 16. Among men, excess risk was observed for industries including plumbing, heating, and air conditioning (odds ratio [OR], = 2.2; 95% confidence interval [CI], 1.0 to 5.0); rubber and plastic products (OR = 3.1; 95% CI, 1.2 to 8.5), motor vehicle parts and supplies (OR = 4.5; 95% CI, 1.2 to 16.5), and occupations including supervisors for transportation and material moving (OR = 6.5; 95% CI, 1.4 to 29.9), material-moving-equipment operators (OR = 1.9; 95% CI, 1.0 to 3.6), automobile mechanics (OR = 1.6; 95% CI, 1.0 to 2.6), painters (OR = 2.7; 95% CI, 1.0 to 7.7), and metal- and plastic-working machine operators (OR = 2.0; 95% CI, 1.1 to 3.4). Among women, significant excess risk was observed for secondary school teachers and record clerks. Housekeepers and butlers and workers in laundering and dry cleaning were also at increased risk. In conclusion, these results suggest that occupational exposures may play a significant role in the risk of bladder cancer.     

Occupational risks for lung cancer among nonsmokers

We conducted a case-control study in 12 European study centers to evaluate the role of occupational risk factors among nonsmokers. We obtained detailed occupational histories from 650 nonsmoking cases (509 females/141 males) and 1,542 nonsmoking controls (1,011 females/531 males). On the basis of an a priori definition of occupations and industries that are known (list A) or suspected (list B) to be associated with lung carcinogenesis, we calculated odds ratios (ORs) for these occupations, using unconditional logistic regression models and adjusting for sex, age, and center effects. Among nonsmoking men, an excess relative risk was observed among those who had worked in list-A occupations [OR = 1.52; 95% confidence interval (C) = 0.78-2.97] but not in list-B occupations (OR = 1.05; 95%), CI = 0.60-1.83). Among nonsmoking women, there was an elevation of risk for list-A occupations (OR = 1.50; 95% CI = 0.49-4.53), although this estimate was imprecise, given that less than 1% of cases and controls were exposed. Exposure to list-B occupations was associated with an increase in relative risk (OR = 1.69; 95% CI = 1.09-2.63) in females, but not in males. Women who had been laundry workers or dry cleaners had an OR of 1.83 (95% CI = 0.98-3.40). Our findings confirm that certain occupational exposures are associated with an increased risk for lung cancer among both female and male nonsmokers; however, knowledge on occupational lung carcinogens is biased toward agents to which mainly men are exposed.     

Occupational risk factors for small bowel carcinoid tumor: a European population-based case-control study

Small bowel carcinoid tumor (SBC) is a rare disease of unknown etiology but with an age-, sex-, and place-specific occurrence that may indicate an occupational origin. A European multicenter population-based case-control study was conducted from 1995 through 1997. Incident SBC cases between 35 and 69 years of age (n = 101) were identified, together with 3335 controls sampled from the catchment area of the cases. Histological review performed by a reference pathologist left 99 cases for study; 84 cases and 2070 population controls were interviewed. The industries most closely associated (a twofold or more odds ratio [OR]) with SBC, taking into account a 10-year time lag after exposure were, among women, employment in wholesale industry of food and beverages (OR, 8.2; 95% confidence interval [CI], 1.9 to 34.9]) and among men, manufacture of motor vehicle bodies (OR, 5.2; 95% CI, 1.2 to 22.4), footwear (OR, 3.9; 95% CI, 0.9 to 16.1), and metal structures (OR, 3.3; 95% CI, 1.0 to 10.4). The identified high-risk occupations with an OR above 2 were shoemakers, structural metal preparers, construction painters and other construction workers, bookkeepers, machine fitters, and welders (men). The OR for regular occupational use of organic solvents for at least half a year was 2.0 (95% CI, 1.0 to 4.2). Exposure to rust-preventive paint containing lead was suggested as another potential occupational exposure (OR, 9.1; 95% CI, 0.8 to 107). This explorative study suggests an association between certain occupational exposures and SBC, but some of these associations could be attributable to chance. All findings should be regarded as tentative.     

Unintended pregnancy and associated maternal preconception, prenatal and postpartum behaviors

Background

This study was conducted to determine the relationship between unintended pregnancy and maternal behaviors before, during and after pregnancy.

Study Design

Data were analyzed from a stratified random sample of 9048 mothers who delivered live born infants between 2001 and 2006 and completed the Pregnancy Risk Assessment Monitoring System (PRAMS) survey 2 to 9 months after delivery. Binary and ordinal logistic regression methods with appropriate survey weights were used to control for socio-demographic factors.

Results

Compared to women with intended pregnancies, mothers with unwanted pregnancies were more likely to consume less than the recommended amount of preconception folic acid [adjusted odds ratio (OR) 2.39, 95% confidence interval (CI) 1.7-3.2], smoke prenatally (OR 2.03, 95% CI 1.5-2.9), smoke postpartum (OR 1.86, 95% CI 1.35-2.55) and report postpartum depression (OR 1.98, 95% CI 1.48-2.64); they were less likely to initiate prenatal care during the first trimester (OR 0.34, 95% CI 0.3-0.5) and breastfeed for 8 or more weeks (OR 0.74, 95% CI 0.57-0.97). Compared to women with intended pregnancies, women with mistimed pregnancies were also more likely to consume inadequate folic acid, delay prenatal care and report postpartum depression.

Conclusion

Even after controlling for multiple socio-demographic factors, unwanted and mistimed pregnancies were associated with unhealthy perinatal behaviors.     

Maternal occupational risk factors for oral clefts. Occupational Exposure and Congenital Malformation Working Group

OBJECTIVES: This study investigated the role of maternal exposures at work during pregnancy in the occurrence of oral clefts. METHODS: The occupational exposures of 851 women (100 mothers of babies with oral clefts and 751 mothers of healthy referents) who worked during the first trimester of pregnancy were studied. All the women were part of a multicenter European case-referent study conducted using 6 congenital malformation registers between 1989 and 1992. In each center, the mother's occupational history, obtained from an interview, was reviewed by industrial hygienists who were blinded to the subject's status and who assessed the presence of chemicals and the probability of exposure. Odds ratios (OR) were estimated by a multivariate analysis including maternal occupation or occupational exposures during the first trimester of pregnancy and possible confounding factors such as center of recruitment, maternal age, urbanization, socioeconomic status, and country of origin. RESULTS: After adjustment for confounding factors, cleft palate only was significantly associated with maternal occupation in services such as hairdressing [OR 5.1, 95% confidence interval (95% CI) 1.0-26.0] and housekeeping (OR 2.8, 95% CI 1.1-7.2). The analysis suggests that the following occupational exposures are associated with orofacial clefts: aliphatic aldehydes (OR 2.1, 95% CI 0.8-5.9) and glycol ethers (OR 1.7, 95% CI 0.9-3.3) for cleft lip with or without cleft palate and lead compounds (OR 4.0, 95% CI 1.3-12.2), biocides (OR 2.5, 95% CI 1.0-6.0), antineoplastic drugs (OR 5.0, 95% CI 0.8-34.0), trichloroethylene (OR 6.7, 95% CI 0.9-49.7), and aliphatic acids (OR 6.0, 95% CI 1.5-22.8) for cleft palate only. CONCLUSIONS: Due to the limited number of subjects, these results must be interpreted with caution. However, they point out some chemicals already known or suspected as reproductive toxins.     

Occupations and breast cancer risk among Chinese women in urban Shanghai

BACKGROUND: Although, an elevated risk of breast cancer has been suggested for a number of occupations, many earlier studies were limited by selection biases, the incomplete assessment of job histories, and the inability to control for confounding. METHODS: We examined the relationship between occupational history and breast cancer risk using data from a population-based case-control study of 1,458 cases and 1,556 age-matched controls (90% response rate) conducted in Shanghai, China. Unconditional logistic regression models were used to derive odds ratios (ORs) and 95% confidence intervals (95% CIs) of breast cancer risk associated with occupations and duration of employment adjusting for non-occupational risk factors. RESULTS: The following occupations were found to be associated with an increased risk of breast cancer: laboratory technicians (OR 9.94, 95% CI 1.20-82.37), telephone and telegraph operators (OR 4.63, 95% CI 1.85-11.59), leather and fur processors (OR 3.25, 95% CI 1.11-9.53), and glass-manufacturing workers (OR 2.08, 95% CI 1.14-3.82). A dose-response pattern for years of employment was observed for leather and fur processors (P = 0.02) and glass-manufacturing workers (P = 0.01). Stratified analyses also revealed dose-response relationships between the risk of breast cancer and years of employment as inspector and product analysts among pre-menopausal women (P = 0.02), and as farmers among post-menopausal women (P = 0.04). CONCLUSIONS: This study found that several occupations are associated with an increased risk of breast cancer among women. Studies examining various occupational exposures in these high-risk occupations are warranted to identify carcinogens that may play a role in the increased breast cancer risk.     

Maternal exposure to arsenic, cadmium, lead, and mercury and neural tube defects in offspring

Arsenic, cadmium, lead, and mercury are neurotoxins, and some studies suggest that these elements might also be teratogens. Using a case-control study design, we investigated the relation between exposure to these heavy metals and neural tube defects (NTDs) in offspring of Mexican-American women living in 1 of the 14 Texas counties bordering Mexico. A total of 184 case-women with NTD-affected pregnancies and 225 control-women with normal live births were interviewed about their environmental and occupational exposures during the periconceptional period. Biologic samples for blood lead and urinary arsenic, cadmium, and mercury were also obtained for a subset of these women. Overall, the median levels of these biomarkers for heavy metal exposure did not differ significantly (P > 0.05) between case- and control-women. However, among women in the highest income group, case-women were nine times more likely (95% confidence interval (CI) 1.4-57) than control-women to have a urinary mercury 5.62 microg/L. Case-women were 4.2 times more likely (95% CI 1.1-16) to report burning treated wood during the periconceptional period than control-women. Elevated odds ratios (ORs) were observed for maternal and paternal occupational exposures to arsenic and mercury, but the 95% CIs were consistent with unity. The 95% CIs of the ORs were also consistent with unity for higher levels of arsenic, cadmium, lead, and mercury in drinking water and among women who lived within 2 miles at the time of conception to industrial facilities with reported emissions of any of these heavy metals. Our findings suggest that maternal exposures to arsenic, cadmium, or lead are probably not significant risk factors for NTDs in offspring. However, the elevated urinary mercury levels found in this population and exposures to the combustion of treated wood may warrant further investigation.     

Lung cancer in motor exhaust-related occupations

The association between employment in motor exhaust-related occupations and the risk for lung cancer was examined in 2,291 male cases of lung cancer and 2,570 controls in data pooled from three U.S. case control studies carried out by the National Cancer Institute between 1976 and 1983. Most analyses were limited to subjects providing direct, in-person interviews, including 1,444 cases and 1,893 controls. For those providing direct interviews and employed 10 years or more in motor exhaust-related (MER) occupations, the age, smoking, and study area adjusted odds ratio (OR) for lung cancer was 1.5 (95% CI = 1.2-1.9). Risk was elevated for truck drivers (OR = 1.5; 95% CI = 1.1-1.9) and for other MER occupations (OR = 1.4; 95% CI = 1.1-2.0). The odds ratios associated with MER employment of 10+ years were 1.6 (95% CI = 1.2-2.1) for whites and 1.4 (95% CI = 0.9-2.1) for nonwhites; 1.2 (95% CI = 0.7-2.0) [corrected] for those with possible exposure to other recognized or reported lung carcinogens; and 1.6 (95% CI 1.2-2.1) for those without such exposure. The 50% excess risk for lung cancer associated with employment in motor exhaust-related occupations could not be explained by greater use of cigarettes or by other occupational exposures among these workers.     

Occupational risk factors for renal cell cancer: a case--control study in northern Italy

Relatively little is known about occupational and other risk factors for renal-cell carcinoma (RCC). Associations between RCC and occupations, exposures and other factors were investigated in a hospital-based case-control study in Bologna (central-northern Italy). Between 1986 and 1994, 324 histologically confirmed RCC cases were diagnosed at Policlinico S. Orsola-Malpighi in patients from the Province of Bologna. Corresponding control subjects admitted to the same hospital with any diagnosis except RCC were matched for sex, age, and residency. We studied the 249 cases and 238 controls for whom detailed information on occupational history, diet, smoking habits, alcohol and drug intake was obtained. At conditional logistic regression, among males (167 matched pairs), significant matched odds ratios (OR) were found, after adjusting for cigarette smoking and alcohol intake, for high body-mass index BMI (third quartile: OR, 4.91; confidence interval [95% CI], 1.56-15.5; last quartile: OR, 4.42; 95% CI, 1.48-13.18), railway workers (OR, 10.14; 95% CI, 1.46-70.17) and asbestos exposure (OR, 7.11; 95% CI, 1.46-34.51); nearly significant OR were found for managers (OR, 3.59; 95% CI, 0.82-15.59) and metal workers (OR, 2.21; 95% CI, 0.99-5.37). Among females (52 pairs), significant OR were found for BMI > 25.4 (OR, 8.46; 95% CI, 1.02-68.0). Railway workers (on or near to trains) may have increased risk of developing RCC, possibly due to asbestos exposure. Studies are required on possible risks encountered by railway (and metal) workers and by managers.     

Occupational risk factors for mycosis fungoides: a European multicenter case-control study

Mycosis fungoides (MF) is a rare disease with an unknown etiology. Its distribution suggests that occupational exposures may play a role. In the present study, we searched for occupational factors associated with MF. A European multicenter case-control study on seven rare cancers, including MF, was conducted from 1995 to 1997. Patients between 35 and 69 years of age diagnosed with MF (n = 134) were identified and their diagnoses were checked by a reference pathologist who classified 83 cases as definitive, 35 cases as possible, and 16 cases as not histologically verified. Of the 118 histologically verified cases, 104 were interviewed, of which 76 were definitive cases. As controls, we selected population controls and colon cancer controls to serve all seven case groups. Altogether, 833 colon cancer controls and 2071 population controls were interviewed. The response rate was 91.5% for cases (76 of the 83 definitive cases), and 66.6% for controls. A high risk of MF for men was observed in the industries of other non-metallic mineral products (Odds Ratio [OR] 5.3, 95% confidence interval [CI] = 1.7-16.2) and of wholesale trade (OR 3.6, 95% CI = 1.3-10.5). A high risk was found for female employees in the sector of pulp paper manufacture (OR 14.4, 95% CI = 2.2-95.1). The male occupations with the highest risks were glass formers, potters, and ceramics workers (OR 17.9, 95% CI = 5.4-59.4) and technical salesmen (OR 8.6, 95% CI = 2.4-30.8). For women, the occupations associated with the highest risks were government executives (OR 4.8, 95% CI = 1.0-22.6) and railway and road vehicles loaders (OR 3.9, 95% CI = 1.0-14.0). The results suggest that some occupational factors are associated with MF. Working as glass formers, pottery, and ceramics workers carried the highest risk, and these findings deserve further attention and replication. Females working in the paper and pulp industries may also be exposed to carcinogens of relevance to MF.     

Spontaneous abortions among Finnish flight attendants.

We conducted a retrospective cohort study to investigate whether work as a cabin attendant is related to an increased risk for spontaneous abortion. Data on female cabin crew members were linked to medical records on pregnancies. There were 1751 eligible pregnancies for the final analysis. Flight attendants who worked during early pregnancy had a slightly elevated risk of spontaneous abortion, as compared with attendants who were pregnant outside a time span of active flying (odds ratio [OR] = 1.3; 95% confidence interval [CI], 0.9 to 1.8). During the earliest years of the study period (1973 through 1977), the risk seemed to be decreased (OR = 0.4; 95% CI, 0.2 to 1.1), whereas during the later years (1978 through 1994) the risk was increased (OR = 1.6; 95% CI, 1.1 to 2.4). The results are in agreement with earlier studies, showing suggestive evidence of a slightly increased risk of spontaneous abortion among female cabin crew members.     

Risks of asthma associated with occupations in a community-based case-control study

The aim of this study was to identify occupational risk groups which might usefully be targeted for occupational asthma surveillance and control, using a community-based case-control approach. Data on previous and current occupations held by subjects were analyzed for 787 adult patients with bronchial asthma and 1591 nonasthmatic patient controls, aged 20-54 years, belonging to the three major races (Chinese, Malays, and Indians) in five outpatient primary care polyclinics. Odds ratios (OR) and 95% confidence intervals (95% CI) of association were adjusted for sex, age, race, smoking, and clinical atopy. No associated risks of asthma were found for clerical or sales workers in general. Significantly reduced risks of association with asthma were found for professional, technical, administrative, and managerial occupations (OR, 0.62; 95% CI, 0.47-0.82). The associated risks of asthma were generally elevated for service workers (OR, 1.35; 95% CI, 1.04-1.74) and manufacturing production and related workers (OR, 1.49; 95% CI, 1.23-1.81). Among them, increased risks were observed for cleaners, particularly municipal cleaners and sweepers (OR, 1.91; 95% CI, 1.22-2.99), textile workers (OR, 5.83; 95% CI, 1.93-17.57), garment makers (OR, 1.61; 95% CI, 1.01-2.58), electrical and electronic production workers (OR, 1.36; 95% CI, 1.06-1.75), printers (OR, 2.24; 95% CI, 1.17-4.31), and construction/renovation workers (OR, 2.24; 95% CI, 1.30-3.85). The odds ratio of association of asthma with exposures in service and production-related occupations overall, relative to the “nonexposed” reference group of nonmanual professional/technical, administrative/managerial, clerical, and sales occupations, was estimated to be 1.72 (95% CI, 1.36-2.19); the estimated population attributable risk was 0.33 (95% CI, 0.22-0.44). © 1994 Wiley-Liss, Inc.     

Maternal occupational exposure to electromagnetic fields before, during, and after pregnancy in relation to risks of childhood cancers: findings from the Oxford Survey of Childhood Cancers, 1953-1981 deaths

BACKGROUND: The concern that maternal exposure to electromagnetic fields (EMF) might be related to childhood cancer risks, particularly leukemia risks. METHODS: Maternal occupational data already collected as part of the Oxford Survey of Childhood Cancers have been reviewed. Information on occupations held before, during, and after the pregnancy was sought for 15,041 children dying of cancer in Great Britain in the period 1953-1981, and for an equal number of matched controls. Each period of working was classified under one of five headings: (1) sewing machinist; (2) textile industry workers (other than sewing machinists) with likely exposures to EMF; (3) other machinists and other jobs with likely "higher" EMF exposure; (4) other jobs with likely exposure to some EMF, and (5) jobs with little potential for EMF exposure. RESULTS: Relative to risks in the children of mothers who held occupations with little potential for EMF exposure during pregnancy (a category that included housewives), risks of all childhood cancers were close to unity both for the children of sewing machinists (22 case and 31 control mothers, RR 0.72, 95% CI 0.42 to 1.25) and for the children of other machinists with likely "higher" EMF exposures (44 case and 47 control mothers, RR 0.93, 95% CI 0.61 to 1.41). Corresponding risks for all childhood leukemias and for all childhood brain cancers were similarly unexceptional. Simultaneous adjustment for social class, maternal age at birth of child, and sibship position had little effect. CONCLUSIONS: The study findings did not indicate that maternal occupational exposure to EMF during pregnancy is a risk factor for childhood leukemias, childhood brain cancers, or the generality of all childhood cancers.     

Paternal occupational exposure around conception and spina bifida in offspring

A multi-center case-referent study was conducted on the relation between paternal occupational exposure and spina bifida in offspring. Cases were born between 1980 and 1992 in The Netherlands. Referents were recruited from hospitals and from the general population. Postal questionnaires were used to gather information on occupation and potential confounders. Through job-specific telephone interviews with 122 case fathers and 411 referent fathers, detailed exposure information was collected on specific tasks, the use of chemical or physical agents, frequency of exposure, and use of protective equipment. The study yielded statistically significant associations between spina bifida and low exposure to welding fumes (OR = 1.6, 95% CI: 1.0–2.6) and low exposure to UV radiation during welding (OR = 2.6, 95% CI: 1.2–5.6), and suggestive findings of an association between spina bifida and moderate or high exposure to cleaning agents, moderate or high pesticide exposure (OR = 1.7, 95% CI: 0.7–4.0), and stainless steel dust (OR = 2.0, 95% CI: 0.8–5.2). No associations were identified for other paternal occupational exposures, such as organic solvents. Am. J. Ind. Med. 32:283-291, 1997. © 1997 Wiley-Liss, Inc.     

Occupational determinants for rheumatoid arthritis

OBJECTIVES: The aim of the present study was to evaluate possible occupational determinants for rheumatoid arthritis according to lifetime occupational history. METHODS: The cases were identified retrospectively from 1980 to 1995 at the University Hospital in Link?ping, Sweden. The study comprised 422 cases and 859 randomly selected referents. Exposure data were collected through a postal questionnaire. RESULTS: For men, occupations with increased, although nonsignificant, odds ratios (OR) were farmers or farm workers [OR 1.8, 95% confidence interval (95% CI) 1.0-3.5], textile workers (OR 2.0, 95% CI 0.3-16.2), asphalters (OR 14.0, 95% CI 1.2-799.0 without latency requirement), and employees at service stations (OR 2.2, 95% CI 0.5-9.5). Among the women, hairdressers and beauticians (OR 2.7, 95% CI 0.8-8.6) had an increased risk for rheumatoid arthritis, as well as those exposed to hairdressing chemicals (OR 3.0, 95% CI 1.0-9.4) and meat products (OR 2.0, 95% CI 1.0-4.0). CONCLUSIONS: Several of the findings in this study are in accordance with those of previous studies. The increased risks of rheumatoid arthritis for asphalters and employees at service stations are however new associations previously not described in the literature.     

Antiretroviral prophylaxis of health care workers at two urban medical centers

We examined the influence of job category, source patient HIV status, and exposure type as predictors of whether health care workers initiated antiretroviral prophylaxis after potential blood-borne pathogen exposures. Of 639 exposures over an 18-month period, 82 individuals (13%) elected to receive prophylaxis, of whom 66% took medications for fewer than 96 hours and 12% completed a 4-week course. Reasons for early drug discontinuation included confirmation of source patient HIV-negative serological status (65%), gastrointestinal side effects (13%), headache (4%), and personal decision after counseling/other input (18%). Individuals exposed to HIV-positive source patients were more likely to initiate prophylaxis (odds ratio [OR], 5.1; 95% confidence interval [CI] 2.6 to 9.9). Licensed nurses were less likely than others to accept prophylaxis (OR, 0.5; 95% CI, 0.3 to 0.8), whereas physicians and medical students were more likely to accept prophylaxis (OR, 1.9; 95% CI, 1.1 to 3.3).     

Are women with an unintended pregnancy less likely to breastfeed?

OBJECTIVE: To examine the association between unintended pregnancy and the initiation and duration of breastfeeding. STUDY DESIGN: This was a secondary data analysis of the 1995 Cycle 5 of the National Survey of Family Growth. POPULATION: We studied 6733 first singleton live births to US women aged 15 years to 44 years. OUTCOMES: Using the 1995 Institute of Medicine definitions, pregnancies were classified as intended or unintended; unintended pregnancies were further categorized as either mistimed or unwanted. We measured initiation of breastfeeding and duration of nonexclusive breastfeeding for at least 16 weeks. RESULTS: In this study, 51.5% of women never breastfed, 48.5% initiated breastfeeding, and 26.4% of all women continued breastfeeding for at least 16 weeks. US women with unwanted unintended pregnancies were more likely not to initiate breastfeeding (odds ratio [OR] = 1.76; 95% CI, 1.26-2.44) and more likely not to continue breastfeeding (OR = 1.69; 95% CI, 1.12-2.55) than women with intended pregnancies. White women with unwanted unintended pregnancies were more likely not to breastfeed than those with intended ones (initiation: OR = 2.50; 95% CI, 1.54-4.05; continuation: OR = 2.56; 95% CI, 1.34-4.87). This finding was not seen for black or Hispanic women. CONCLUSIONS: In the United States, women with unwanted pregnancies were less likely either to initiate or to continue breastfeeding than women with intended pregnancies. A strong inverse association between unwanted pregnancies and breastfeeding was observed only for white women. Education for women with unintended pregnancies may improve breastfeeding rates and subsequently, the health of women and infants.     

Risk factors for female infertility in an agricultural region

BACKGROUND: Recent studies have suggested that agricultural occupations or exposure to pesticides may impair female fertility. METHODS: The Fertility Risk Factor Study retrospectively examined agricultural and residential exposures and the risk of female infertility. Cases and controls (N = 322 each) came from women who sought treatment at a large group medical clinic in Wisconsin. Women and their male partners provided information on health, occupational and lifestyle exposures in response to a telephone interview during 1997-2001. RESULTS: Mixing and applying herbicides 2 years before attempting conception was more common among infertile women (odds ratio [OR] = 27; 95% confidence interval [CI] = 1.9-380), as was the use of fungicides (OR = 3.3; CI = 0.8-13). Residing on a farm, ranch or in a rural area during this time period was protective of female fertility. Households supplied with central Wisconsin groundwater were at less risk for infertility than households using municipal sources (OR = 0.6; CI = 0.4-0.9). Behavioral risk factors included alcohol consumption (OR = 1.8; 1.2-2.5), smoking (1.6; 0.9-2.9), passive smoke exposure (1.8; 1.2-2.5), steady weight gain in adult life (3.5; 2.0-6.1), and having a male partner over the age of 40 (4.5; 1.2-16.3). Drinking 3 or more glasses of milk per day was protective of female fertility (0.3; 0.1-0.7). CONCLUSION: These results suggest that certain agricultural, residential and lifestyle choices may modify the risk of female infertility.     

Occupation as a risk factor for uveal melanoma in Germany

OBJECTIVE: This study explored occupational risks linked to uveal melanoma. METHODS: The analysis pooled data from two case-referent studies (hospital- and population-based) conducted in Germany between 1995 and 1998, with incident cases matched with several referents by age, gender, and region of residence. The subjects were contacted through personal or telephone interviews. Their exposure status was based on their occupational history. Dichotomous coding for the main task and categorization into different occupational classification systems was performed. Altogether of 118 cases and 475 referents were included. Adjusted odds ratios were calculated by conditional logistic regression. RESULTS: Relevant occupations included food, beverage, and tobacco processors [odds ratio (OR) 4.7, 95% confidence interval (95% CI) 0.99-22.0] and miners (OR 2.3, 95% CI 0.92-5.99) among the men and station, engine and heavy equipment operators and freight handlers (OR 2.5, 95% CI 0.94-6.58) and medical, dental, pharmaceutical and veterinary workers (OR 2.1, 95% CI 0.71-6.02) among the women according to the International Standard Classification of Occupations, whereas, according to the European Industrial Classification, the relevant occupations were the food industry (OR 3.4, 95% CI 1.08-10.5) and the chemical and pharmaceutical industry (OR 2.8, 95% CI 1.01-7.78) among the men and machine production (OR 3.2, 95% CI 0.96-10.7) and health and veterinary sector (OR 2.4, 95% CI 0.97-5.71) among the women. CONCLUSIONS: These analyses support the potential role of occupational exposure as a risk factor for uveal melanoma. The findings must be interpreted carefully since the exposure was assessed indirectly.