Indoor NO2, temperature, and humidity in relation to maternal stress, sleep, and cognitive performance during pregnancy

Abstract

Background: Evidence characterising indoor environmental exposures and their effects on maternal neurobehavioural well-being during pregnancy remains scarce. Aim: To estimate the associations between indoor residential environmental exposures (nitrogen dioxide (NO2), temperature, and relative humidity (RH)) and maternal neurobehavioural well-being (measured as perceived stress, sleep quality, and cognitive performance). Methods: We included pregnant individuals (n = 906) from the population-based Barcelona Life Study Cohort (BiSC) who were recruited from 2018 to 2021. Weekly average indoor residential NO2 concentrations, temperature, and RH were objectively measured in participants’ homes at ∼ 12 and ∼ 32 weeks of gestation using indoor monitoring devices. Linear, negative binomial, and mixed-effects regression models estimated the associations between indoor environmental exposures and perceived stress (10-item Perceived Stress Scale [PSS-10]), sleep quality (Pittsburgh Sleep Quality Index [PSQI]), and cognitive performance (N-back reaction time and Primary Mental Abilities-Revised [PMA-R]); PSQI was assessed at both visits, while PSS-10 and cognitive tests were performed at ∼ 32 weeks of gestation only. Results: After covariate adjustment, higher indoor NO2 exposure was associated with higher perceived stress (0.66 points (95 % confidence interval [CI] 0.11, 1.21; p = 0.019)) and a greater increase in PSS-10 scores for a NO2 interquartile range increase (11.2 µg/m3) but not with sleep quality or cognitive performance. Indoor temperature and RH metrics, including nighttime minima and maxima, were not associated with any outcome. Conclusion: Our findings suggest an association between indoor NO2 concentration and prenatal perceived stress, indicating that the residential environment may be a relevant factor in maternal antenatal health that warrants further investigation.