Effect of Cigarette Smoking on Sperm Parameters in Men With Idiopathic Infertility

Background: Several studies have reported that cigarette smoking affects sperm parameters, especially semen quality, but their results are contradictory. Objective: This retrospective study aims to evaluate the relationship of sperm parameters with smoking in men with idiopathic infertility. Materials and Methods: This retrospective study was conducted on 1744 infertile men with at least one year of idiopathic infertility. They were divided into two groups of smokers (n=379) and non-smokers (n=1365) according to their smoking habits and based on their inclusion and exclusion criteria. The semen analysis was extracted from subjects’ medical records, and the collected data were analyzed in SPSS V. 19 software. Results: Smoking significantly reduced semen volume in smokers (2.88±1.50 mL) compared to non-smokers (3.28±1.77 mL) (P=0.002). There was a significant decrease in sperm motility in smokers (36.1±21.9%) compared to non-smokers (34.4±19.6%) (P=0.009). However, the association of smoking with sperm motility between men with normal and abnormal semen volumes was not statistically significant, and there was no significant difference in sperm count and morphology between infertile smokers and non-smokers (P>0.05). Conclusion: Smoking causes a significant reduction in semen volume, but has no significant effect on sperm count, morphology, and motility in men with abnormal and normal semen volume.