A case-control study of the factors affecting male infertility.

BACKGROUND/AIM Infertility is defined as the inability to conceive after at least 1 year of unprotected intercourse. In about one third of infertile couples, a male factor is the primary problem. Thus, the present study aimed to determine the most common risk factors for male infertility in Iranian men. MATERIALS AND METHODS This case-control study included 268 men attending an infertility clinic in Shiraz, Iran. In this study, 161 fertile men were compared with 108 infertile ones regarding risk factors such as smoking habits, drug consumption, hernia, varicocele, job, and BMI. The data were analyzed using logistic regression analysis and t-test. RESULTS The mean age of the fertile and infertile participants was 37.5 ± 7 and 36.3 ± 10, respectively. Our findings demonstrated a statistically significant relationship between male infertility and hernia, varicocele, taking ranitidine, job, and BMI. With an increase of 1 cigarette per day, there was a 1% decrease in the motility of the sperm. Moreover, with an increase of 1 year of cigarette smoking, 800,000 sperm are lost. CONCLUSION The results revealed varicocele and hernia as the most common risk factors in men attending the infertility clinics in Shiraz. In addition, strenuous work could cause testicular injury.