Decreased sperm motility is associated with air pollution in Salt Lake City.

OBJECTIVE

To study the correlation between indices of air pollution and sperm parameters.

DESIGN

Ecological study.

SETTING

Contained geographic area.

PATIENT(S): Resident men presenting for semen analysis or artificial insemination.

INTERVENTION(S): Analysis of levels of particulate air pollution (particulate matter [PM] 2.5) over a five-year period in relation to sperm parameters obtained from semen analyses and separately in relation to sequences of sperm parameters at the time of semen preparations for artificial insemination. To account for the duration of spermatogenesis (72 days), "corrected" variables were created by shifting backward 1, 2, 3 and 4 months each of the semen parameters. The final analysis corrected for season of the year and current temperature.

MAIN OUTCOME MEASURE(S): Sperm concentration, sperm motility and sperm morphology.

RESULT(S): The study included 1,699 semen analyses and 877 inseminations. PM 2.5 levels were highest in the winter months, when the ambient temperature was the lowest. Semen analysis data showed that values of PM 2.5 were negatively correlated to sperm motility two months and three months following the recording of the PM 2.5 values. Artificial insemination data also showed that sperm motility correlated negatively with PM 2.5 values recorded three months previously.

CONCLUSION(S): Both semen analysis and sperm parameters data obtained from men presenting for multiple inseminations over time showed that air pollution is associated with reduced sperm motility two to three month after exposure.