BACKGROUND

In recent decades, the quality of male semen has decreased worldwide. Air pollution has been linked to lower semen quality in several studies. However, the effects of atmospheric pollutants on different semen characteristics have not always been consistent. The aim of this study was to investigate the association between the Air Quality Index (AQI) and six atmospheric pollutants (PM, PM, SO, NO, CO, and O), semen quality, and their key exposure window periods.

METHODS

This study included 1711 semen samples collected at the reproductive clinics of the First Affiliated Hospital of Shanxi Medical University in Taiyuan, Shanxi, China, from October 10, 2021, to September 30, 2022. We evaluated the association of AQI and six atmospheric pollutants with semen quality parameters throughout sperm development and three key exposure windows in men using single-pollutant models, double-pollutant models, and subgroup analyses of semen quality-eligible groups.

RESULTS

Both the single-pollutant model and subgroup analyses showed that PM, CO, and O levels were negatively correlated with total and progressive motility. At 70-90 d before semen collection, CO exposure and semen volume (β =-1.341, 95 % CI: -1.805, -0.877, P <0.001), total motility (β =-2.593, 95 % CI: -3.425, -1.761, P <0.001), and progressive motility (β =-4.658, 95 % CI: -5.556, -3.760, P <0.001) were negatively correlated. At 0-9 days before semen collection, CO was negatively correlated with normal morphology (β =-3.403, 95 % CI: -5.099, -1.708, P <0.001). Additionally, the AQI was adversely associated with total and progressive motility in subgroup analyses of the semen quality-eligible groups.

CONCLUSIONS

During the entire sperm development process, multiple air pollutants were determined to have an adverse correlation with semen quality parameters. AQI was significant marker for the combined effects of various atmospheric pollutants on male reproductive health.