Environmental PM2.5 Exposure and Socioeconomic Deprivation Are Independent Risk Factors for Impaired Semen Parameters.
Level 3 - non-randomized controlled study
Retrospective observational cohort study
PubMed 40846186 · doi:10.1016/j.urology.2025.08.034
What was done
A retrospective cohort study analyzed 8,446 men undergoing initial fertility evaluation with semen analysis between 2002 and 2020 at a single academic health system. Semen volume, sperm concentration, motility, morphology, and total motile sperm count were assessed. Socioeconomic Deprivation Index and average ambient PM2.5 exposure during the 74 days preceding the index semen analysis were estimated based on residential address. Differences across socioeconomic strata were compared using ANOVA, and multivariable logistic regression adjusted for age, race/ethnicity, and body mass index to evaluate associations with abnormal semen parameters.
What was found
Overall, 1,258 men (14.9%) experienced moderate-to-hazardous PM2.5 exposure during the 74-day spermatogenic window. These men had higher socioeconomic deprivation scores (median 0.23 vs 0.22, P = .001) and significantly lower total motile sperm count (median 59.0 M vs 72.0 M, P < .001), along with lower ejaculate volume, sperm concentration, and motility. Men with high socioeconomic status had higher total motile sperm counts than those with low socioeconomic status (median 75.0 M vs 62.6 M, P < .001). After adjusting for age, race/ethnicity, and BMI, both higher Deprivation Index (OR 2.81, 95% CI 1.61–4.90, P < .001) and higher average daily PM2.5 exposure (OR 1.05 per unit increase, 95% CI 1.03–1.08, P < .001) remained independently associated with increased odds of decreased total motile sperm count.
Why it matters
This study demonstrates that both environmental air pollution and neighborhood-level socioeconomic disadvantage independently predict worse semen quality in men presenting for fertility evaluation, highlighting external environmental and social contributors to male reproductive health.
Limits
The study is retrospective and restricted to men already seeking fertility care at a single health system, limiting generalizability to the broader population. Exposure assessment relied on residential address rather than personal or workplace monitoring. Unmeasured lifestyle factors, occupational exposures, and medical comorbidities were not fully accounted for in the multivariable models.
Cited by
- context The lifespan of sperm is approximately 90 days, and the human egg is most susceptible to environmental influences during the 60 days prior to conception.