Paternal Occupational Lead Exposure and Pregnancy Outcome

Self-reported reproductive histories of male employees of a lead-zinc smelter were related to pre-conception measures of lead exposure to examine associations between paternal occupational lead exposure and adverse pregnancy outcome. The participants reported 2,021 pregnancies which resulted in 1,684 normal live births, 12 stillbirths, 30 birth defects, 203 spontaneous abortions, and 92 "other" outcomes. Birth defects and stillbirths were combined for the analysis. The risk of a stillbirth or birth defect was elevated for pre-conception employment in a high-lead-exposure compared with a low-lead-exposure job (odds ratio = 2.7, 95% confidence interval = 0.7, 9.6). A similar risk was found for pre-conception blood lead levels of 25-39 µg/dL and >/= 40 µg/dL when compared with blood lead levels of < 25 µg/dL (OR = 2.9, 95% CI = 0.6, 13.3, and OR = 2.5, 95% CI = 0.5, 11.6, respectively). No association was found between pre-conception lead exposure and spontaneous abortion. A relatively low response rate to the questionnaire and potentially erroneous reporting of reproductive outcomes by male workers are limitations of the study.