Associations between indoor temperature and noise and semen parameters among participants in the US-based general population Growing Up Today Study

Abstract

BACKGROUND AND AIM: Multiple environmental exposures have been suggested as important determinants of decreases in semen quality. However, very little is known regarding the impacts of non-occupational noise and indoor temperature exposures. Our aim was to explore these associations in a general population cohort of young men in the United States. METHODS: Participants were members of the prospective Growing Up Today Study. Exposures to noise, temperature, and relative humidity were collected every 5 minutes for 90 days in the main room of each home with a NetAtmo weather station. Semen samples collected at home were sent by express shipping to the Massachusetts General Hospital Andrology Laboratory; sperm concentration and morphology were assessed via computer-aided and manual methods. Associations per interquartile range (IQR) were assessed in three-exposure generalized linear models, adjusted for age, race, and body mass index. RESULTS:The first 82 participants were included in analyses (average age 35.6 years). The average sperm concentration was 56.5 (SD=36.9) M/ml and the percent normal morphology was 4.5% (SD=2.1). The average 90-day average noise level was 62.5 dB (SD=8.0), temperature was 22.0°C (SD=1.9) and relative humidity was 54.0% (SD=8.2). There was little evidence that the exposures were associated with sperm concentration (-1.91, 95%CI:-12.44, 8.63 per 9.83dB of noise; -3.73, 95%CI: -14.93, 7.46 per 2.53°C; 9.25, 95%CI: -0.78, 19.27 per 9.63% relative humidity) or % normal morphology (0.04, 95%CI: -0.58, 0.66 per 9.83dB of noise; -0.59, 95%CI: -1.23, 0.05 per 2.53°C; 0.04, 95%CI: -0.53, 0.61 per 9.63% relative humidity). CONCLUSIONS:In this cohort of general population US men, temperature, humidity, and noise in the 90 days before producing a semen sample were not associated with measures of semen quality. The impact of these exposures may be limited to sensitive time windows. KEYWORDS: Noise, Temperature, Relative Humidity, Reproductive Outcomes, Male, environmental epidemiology