Water Disinfection By-Products and the Risk of Stillbirth: A Population-Based Cross-Sectional Study in Taiwan

Abstract

ISEE-172 Objective: To assess the risk of stillbirth in relation to prenatal exposure to water chlorination by-products. Material and Methods: We conducted a nationwide cross-sectional study of 396,049 Taiwanese births in 2001 to 2003 using information from the Birth Registry and Waterworks Registry in Taiwan. We compared the risk of stillbirth in 4 disinfection by-product exposure categories based on the levels of total trihalomethanes (TTHMs) representing high (TTHMs 20+ μg/L), medium (TTHMs 10–19 μg/L), and low exposure (TTHMs 5–9 μg/L), and 0 to 4 μg/L as the reference category. Results: The risk of stillbirth was related to the exposures of interest. In logistic regression analysis, after adjusting for maternal age, plurality, and population density of the municipality where the mother lived during pregnancy, the odds ratio (OR) for stillbirth was 1.07 (95% CI 0.98–1.17) for medium exposure and 1.06 (95% 0.96–1.17) for high exposure compared with reference category. Conclusions: The risk of stillbirth in Taiwanese women is slightly related to exposure to chlorination by-products in drinking waters.