Exposure to night-time light pollution and risk of prolonged duration of labor: A nationwide cohort study

Abstract

Background: Light pollution (LP) is a ubiquitous environmental agent that affects more than 80% of the world's population. This large nationwide cohort study evaluates whether exposure to LP can influence obstetric outcomes. Methods: We analyzed Austrian birth registry data on 717 113 cases between 2008 and 2016 and excluded cases involving day-time delivery, <23 + 0 gestational weeks, and/or birthweight <500 g, induction of labor, elective cesarean, or cases with missing data. The independent variable, that is, degree of night-time LP, was categorized as low (0.174 to <0.688 mcd/m2), medium (0.688 to <3 mcd/m2), or high (3 to <10 mcd/m2). Duration of labor and adverse neonatal outcomes served as outcome measures. Results: Cases in regions with high LP (odds ratio [OR], 1.43; 95% confidence interval [CI], 1.30-1.57) and medium LP (OR, 1.22; 95% CI, 1.14-1.31) showed increased odds of prolonged labor (P <28 + 0 weeks was also associated with the degree of LP (P =.04). Conclusions: Night-time LP negatively interferes with obstetric outcomes. The perceived influence of LP as an environmental agent needs to be re-evaluated to minimize associated health risks.