Pregnancy outcome among women working in laundries and dry-cleaning shops using tetrachloroethylene.

Case-referent studies were performed within two cohorts of women engaged in laundry or dry-cleaning work. The aim was to elucidate if tetrachloroethylene (perchloroethylene) exposure increased the risk of adverse pregnancy outcome (spontaneous abortion, perinatal death, congenital malformations or birth weight less than 1,500 g). Pregnancies and outcomes were identified in national registers and exposure data were obtained from the women by postal questionnaires. Response rates were 75-88%. Conditional logistic regression analysis of the total material yielded an adjusted odds ratio for tetrachloroethylene exposure during the first trimester of 1.1 (95% confidence interval 0.6-2.0) when several potential confounding factors were accounted for. The total material included few highly exposed pregnancies and a limited number of cases of specific adverse outcomes. Consequently, the results do not invalidate the recommendation that tetrachloroethylene should be handled with caution by women in childbearing ages.