Lowell E. Sever

Parental consumption of contaminated sport fish from Lake Ontario and predicted fecundability.

Wildlife studies suggest that consumption of contaminated fish from the Great Lakes may expose humans to polychlorinated biphenyls and persistent chlorinated pesticides. To assess whether time to pregnancy or fecundability is affected, we conducted a telephone survey in 1993 with female members of the New York State Angler Cohort Study who were considering pregnancy between 1991 and 1994 (N = 2,445). Among the 1,234 (50%) women who became pregnant, 895 (73%) had a known time to pregnancy. Upon enrollment into the cohort in 1991, both partners reported duration and frequency of Lake Ontario sport fish consumption. We estimated lifetime exposure to polychlorinated biphenyls from recent consumption and used a discrete-time analog of Cox proportional hazards analysis to estimate conditional fecundability ratios and 95% confidence intervals (CIs) for fish consumption among couples with complete exposure data who discontinued birth control to become pregnant (N = 575). Maternal consumption of fish for 3-6 years was associated with reduced fecundability (fecundability ratio = 0.75; 95% CI = 0.59-0.91), as was more than a monthly fish meal in 1991 (fecundability ratio = 0.73; 95% CI = 0.54-0.98). Our findings suggest that maternal but not paternal consumption of contaminated fish may reduce fecundability among couples attempting pregnancy.

Pesticide Exposures and Fetal Death: A Review of the Epidemiologic Literature

Despite considerable concern regarding the effects on reproductive outcome of exposures to pesticides, convincing evidence for the developmental toxicity of occupational and environmental pesticide exposure in humans is lacking. In this comprehensive review of the English language epidemiologic literature, we summarize studies that have examined potential associations between fetal deaths (both spontaneous abortions and stillbirths) and specific pesticides, as well as maternal and paternal employment in occupations with potential for exposure. While many of the epidemiologic studies to date suffer from methodologic problems, the data are suggestive of increased risks of fetal deaths associated with pesticides in general and maternal employment in the agricultural industry. There is a clear need for epidemiologic research that focuses on specific pesticide products or chemical families, with improved exposure assessment. The potential role of solvents in developmental toxicity associated with pesticide use by both males and females should also be considered.

The New York Angler Cohort Study: Exposure Characterization and Reproductive and Developmental Health

The New York State Angler Study will evaluate the association between past and current consumption of contaminated fish from Lake Ontario and both short- and long-term health effects in a population-based cohort. It will measure fish consumption and reproductive and developmental health among 10,518 male anglers and 6,651 of their wives or partners, as well as among 913 female anglers. To characterize exposure among subgroups of the cohort, further analytical methods were developed and implemented to measure specific polychlorinated biphenyls (PCB) congeners, methylmercury, and other substances in biological samples. Exposure assessment has been completed for a stratified random sample of 321 anglers. In addition, analyses for 79 congeners of PCBs are complete for 177 anglers. A special study of duck andturtle consumers currently is underway. Telephone interviews have been completed with 2,454 of the 2,999 women who planned a pregnancy between 1991 and 1994. The entire cohort of male anglers, partners of male anglers, and female anglers has been submitted for matching with the New York State live birth and fetal death registries to obtain lifetime reproductive histories. A medical record abstraction study will assess perinatal and developmental outcomes among the 3,442 births that occurred between 1986 and 1991. Finally, a study of breast milk from currently lactating women is underway, and 215 breast milk samples have been collected from the planned pregnancy subcohort. Progress on each of the study components is discussed herein.

Life-style factors and female infertility.

We summarize the epidemiologic literature on the effect of life‐style factors such as cigarette smoking, alcohol and caffeine consumption, physical exercise, body mass index, and drug use on female infertility. We identified relevant papers through MEDLINE, Index Medicus, and a manual review of reference lists. Risk factors that affect the risk of primary tubal infertility and that were corroborated in two or more studies include use of intrauterine devices (especially the Dalkon Shield) and cigarette smoking. We identified extremes in body size as a risk factor for primary ovulatory infertility. Cocaine, marijuana and alcohol use, exercise, caffeine consumption, and ever‐use of thyroid medications were possible risk factors for various subtypes of primary infertility. Few risk factors have been assessed or identified for secondary infertility or other less common subtypes, such as cervical or endometriosis‐related infertility.

Descriptive epidemiologic features shared by birth defects thought to be related to vascular disruption in Texas, 1996-2002.

BACKGROUND In utero vascular disruptions are thought to be associated with a variety of birth defects. This study examined the descriptive epidemiology of several of those defects using data from a large birth defects registry. METHODS Data on birth defects ascertained from pregnancies in 1996-2002 were obtained from the Texas Birth Defects Registry. Using Poisson regression, we calculated crude and adjusted associations between maternal and infant characteristics and birth defects thought to be related to vascular disruption. We repeated the analysis using isolated cases and cases occurring in mothers <20 years. RESULTS The most commonly shared pattern was observed for plurality and five defects: large intestinal atresia (PR 3.67; CI: 1.63-7.13), renal agenesis (PR 2.05; CI: 1.55-2.65), transverse limb deficiency (PR 1.85; CI: 1.28-2.57), porencephaly (PR 5.18; CI: 2.40-9.87), and Goldenhar syndrome (PR 3.45; CI: 1.04-8.53). Hispanics had the highest prevalence of gastroschisis (PR 1.21; CI: 1.05-1.40), transverse limb deficiency (PR 1.19; CI: 1.01-1.40), microtia/anotia (PR 2.22; CI: 1.83-2.70), and Poland anomaly (PR 1.90; CI: 1.26-2.93). Male infants were at greatest risk for renal agenesis (PR 1.58; CI: 1.40-1.80), porencephaly (PR 1.66; CI: 1.03-2.72), and Poland anomaly (PR 1.52; CI: 1.05-2.21). CONCLUSIONS Our study confirmed findings in previous studies, but also uncovered several new associations.

Acute myelocytic leukemia and prior allergies

The relationship between prior allergies and adult acute myelocytic leukemia was investigated in a population-based case-control study. Based on data from personal interviews of 98 cases and 133 controls, a history of any type of allergy was associated with a significantly decreased risk of acute myelocytic leukemia (OR = 0.35, 95% CI = 0.20-0.60). Risk declined with the total number of specific allergies reported (p less than 0.001), and was reduced in relation to a history of prior asthma, eczema and hives. The implications of these findings in relation to natural immune surveillance against developing neoplasms are discussed.

Early-stage breast cancer treatment among medically underserved women diagnosed in a national screening program, 1992–1995

AbstractBackground. Little research has been conducted on the breast cancer treatment of low income, underserved women. This study was designed to describe initial treatment of breast cancer among low-income women diagnosed through federally funded screening programs in Detroit, Michigan, and the states of New Mexico and California; and to compare the treatment received by program women with early-stage breast cancer with that of all women diagnosed in those regions. Methods. Data from the three screening programs were linked with cancer registry data from the corresponding geographic areas. All women diagnosed between 1992 and 1995 through the state-based screening programs and all women contemporaneously diagnosed with breast cancer in the three regions were studied. Descriptive analyses were done of the proportion of women with breast cancer receiving treatment; the proportion of early-stage breast cancer (stage I or II) cases treated with breast-conserving surgery, and the proportion treated with mastectomy; and among women with breast-conserving surgery, the proportion receiving radiation therapy. Logistic regression models controlled for age and stage at diagnosis, race or ethnicity and geographic region. Results. Less than 2% of program women diagnosed with breast cancer received no treatment. More than two of five women with early-stage breast cancer underwent breast-conserving surgery, with 72% of these women receiving radiation therapy. Multivariate regression analysis revealed that women with stage IIA or IIB breast cancer had lower odds of undergoing breast-conserving surgery than women with stage I (0.51 [95% CI = 0.30–0.87] and 0.36 [95% CI = 0.19–0.70], respectively). Women over age 65 and those with incompletely staged cancer had the lowest odds for receiving radiation therapy after breast-conserving surgery (0.29 [95% CI = 0.09–0.99] and 0.14 [95% CI = 0.03–0.72], respectively). Women diagnosed through the screening programs had odds of undergoing breast-conserving surgery similar to those of all women in the regions (1.11 [95% CI = 0.89–1.39]). Conclusions. Treatment patterns for women diagnosed with early-stage breast cancer through three state-based screening programs appear to have been similar to those reported in the literature. In addition, their treatment appears to have been similar to that of other women during the same time period.

Intergenerational Factors in the Etiology of Anencephalus and Spina Bifida

To test the hypothesis that events and conditions early in womens lives influence their Future risk of producing babies with anencephalus and spina bifida, a case‐control study compared mothers of affected infants with mothers whose infants were normal.

Infecundity and Consumption of Polychlorinated Biphenyl-Contaminated Fish

Abstract Biologic capacity for reproduction, or fecundity, may be threatened by environmental contaminants, especially compounds capable of disrupting endocrine pathways. Telephone interviews that focused on reproductive events were conducted with female members of the New York State Angler Cohort Study who became pregnant between 1991 and 1993 and who reported known time to pregnancy (N = 895; 73%). Consumption of polychlorinated biphenyl-contaminated Lake Ontario sportfish and other factors were ascertained in 1991. The authors classified the women as follows: (a) fecund (time to pregnancy < 12 cycles; n = 723); (b) having resolved infecundity (time to pregnancy > 12 cycles; n = 81); or (c) having unresolved infecundity (time to pregnancy > 12 cycles without pregnancy; n = 94). Adjusted odds ratios for duration of fish consumption for both resolved and unresolved infecundity were elevated (1.46 and 1.19, respectively), although confidence intervals included unity. Frequency of recent fish consumption was associated with an increased risk for select categories, although confidence intervals included one.

Mass screening in low-income populations: the challenges of securing diagnostic and treatment services in a national cancer screening program.

Funding for many mass screening programs for low-income and uninsured populations provides resources for screening tests, yet only rarely does it provide coverage for necessary follow-up diagnostic and treatment services. The National Breast and Cervical Cancer Early Detection Program (NBCCEDP), a federally funded initiative that provides cancer screening to low-income uninsured and underinsured women, covers some diagnostic follow-up tests and no treatment services. We conducted in-depth case studies of seven state programs participating in the NBCCEDP to investigate the strategies and approaches being used to secure diagnostic and treatment services. The results suggest that the program relies on a patc work of resources--at state and local levels--to provide diagnostic and treatment services. This includes a number of components of local safety nets, all of which are unstable and have uncertain futures. Public health disease-screening initiatives need to reconsider the feasibility of continued reliance on case-by-case appeals to the local safety net for diagnostic follow-up and treatment services.