Physical activity and semen quality among men attending an infertility clinic

Abstract

OBJECTIVE

To examine the association between regular physical activity and semen quality.

DESIGN

Prospective cohort study.

SETTING

Couples attending one of three IVF clinics in the greater Boston area during 1993–2003. At study entry, male participants completed a questionnaire about their general health, medical history, and physical activity. Odds ratios (OR) and 95% confidence intervals (CI) were derived using generalized estimating equations models, accounting for potential confounders and multiple samples per man.

PATIENTS

A total of 2,261 men contributing 4,565 fresh semen samples were enrolled before undergoing their first IVF cycle.

INTERVENTION

None.

MAIN OUTCOME MEASURES

Semen volume, sperm concentration, sperm motility, sperm morphology, and total motile sperm (TMS).

RESULTS

Overall, none of the semen parameters was materially associated with regular exercise. Compared with no regular exercise, bicycling ≥5 hours per week was associated with low sperm concentration (OR=1.92, 95%CI=1.03–3.56) and low TMS (OR=2.05, 95%CI=1.19–3.56). These associations did not vary appreciably by age, body mass index, or history of male factor infertility.

CONCLUSIONS

While the present study suggests no overall association between regular physical activity and semen quality, bicycling at levels of ≥5 hours per week was associated with lower sperm concentration and TMS.