Cigarette smoking and its possible effects on sperm.

The possible effects of cigarette smoking on sperm were evaluated by comparison of the quality of sperm from 103 smokers and 135 nonsmokers in a blind study. Smokers were found to possess significantly (P less than 0.001) decreased density (number) and motility of their sperm than nonsmokers. Morphologic abnormalities, particularly bicephalia, although prevalent among individual smokers, did not differ significantly (P greater than 0.9) when a comparison of smokers versus nonsmokers was made as a whole. Based on these observations and those of others demonstrating the presence of the mutagenic properties of smoke condensates, we suggest that decreases in sperm density and motility in cigarette smokers may be reflective of smoke condensate-induced mutagenic spermatogenital alterations.