Residential road traffic noise and pregnancy complications – The NordSOUND study

Abstract

BACKGROUND AND AIM Only few studies have evaluated the effects of exposure to environmental noise on pregnancy. The NordSOUND project utilizes high-quality register data in four Nordic countries to comprehensively study the health effects of environmental and occupational noise. The present study evaluates associations between maternal exposure to road traffic noise during pregnancy and pregnancy complications. METHODS The study included metropolitan areas of Copenhagen, Denmark, Helsinki, Finland, and Gothenburg and Stockholm, Sweden. Data from Oslo, Norway, will soon become available, too. Gestational diabetes, gestational hypertension, and severe and mild pre-eclampsia were used as outcomes. Data sources were national population and patient registers. Residential yearly levels of transport-related noise and air pollution were modelled. Logistic regression analyses, followed by meta-analyses, were adjusted for age, parity, smoking, education, marital status, neighborhood income, traffic-related air pollution, green and blue areas, and other transport noise sources. RESULTS The total number of pregnancies in the final analyses was 417 000. No associations were observed between road traffic noise and gestational hypertension or pre-eclampsia. However, exposure to road traffic noise during pregnancy was associated with an increased risk of gestational diabetes: odds ratio (95 % confidence intervals) in a random effect model was 1.09 (1.03; 1.15) per 10 dB increase in exposure. The analyses will be repeated adding data from Norway. CONCLUSIONS These preliminary results suggest that maternal exposure to road traffic noise during pregnancy increases the risk of gestational diabetes. KEYWORDS Noise, road traffic, pregnancy complications, maternal exposure