Fish consumption and reproductive outcomes in Green Bay, Wisconsin.

Prenatal exposure to polychlorinated biphenyls (PCBs) and reproductive outcome was determined in a population of 1112 women during 1987-1989. The women studied were from the Green Bay, Wisconsin area, thereby providing a population with potential PCB exposure from Lake Michigan sport fish consumption. All women with positive pregnancy tests from two Green Bay prenatal clinics were asked to complete a self-administered questionnaire on fish consumption, health and reproductive history, and other relevant issues and to provide blood samples for PCB analysis. A positive correlation was found between the amount of Lake Michigan fish mothers claimed to consume and their PCB serum levels. After the pregnancy period, reproductive outcome measures (fetal wastage; stillbirths; and birth weight, birth length, head circumference, ponderal index, and birth weight percentiles for live births) were abstracted from hospital labor reports. Typical negative associations between birth size measures and consumption of caffeine, smoking, and alcohol were found. Birth size was positively associated with gestational age, birth order, weight gain during pregnancy, male babies, and rural residence. Birth size was also associated with PCB exposure; however contrary to expectations, a positive association was found (P < 0.044) for most mothers (the exception being those mothers who gained more than 34 lb during their pregnancy). PCB exposures were lower than the other studies that found that birth size was negatively associated with PCB exposure.