Effect of smoking status on seminal parameters and apoptotic markers in infertile men

We assessed semen parameters, sperm apoptotic markers and seminal plasma cotinine in infertile smokers.

A total of 160 men were divided into 4 equal groups, including fertile smokers, fertile nonsmokers, infertile smokers and infertile nonsmokers. Smoking was classified as mild--fewer than 10, moderate--10 to 20 or heavy--more than 20 cigarettes daily. All men underwent semen analysis, and assessment of sperm caspase-9, Smac/DIABLO, DNA fragmentation and seminal plasma cotinine.

Infertile men, particularly smokers, have significantly lower semen variables and significantly higher sperm Smac/DIABLO, caspase-9 activity, the percent of DNA fragmentation and seminal plasma cotinine. The mean number of cigarettes smoked daily and smoking duration significantly correlated positively with sperm Smac/DIABLO, caspase-9 activity, the percent of DNA fragmentation and seminal plasma cotinine, and significantly correlated negatively with tested semen variables. Heavy smoking was associated with a significant increase in sperm Smac/DIABLO, caspase-9 activity and seminal plasma cotinine, and with a significant decrease in tested semen variables compared with those in moderate or mild smokers.

Smoking has a negative impact on semen variables. It is associated with increased sperm caspase-9, Smac/DIABLO and the percent of DNA fragmentation, especially in infertile heavy smokers.