O-4: Occupational Heat Exposures and Male Infertility

Background: In humans, as in most mammals, spermatogenesis is temperature dependent. Experimental studies in animals and humans have demonstrated the role of exogenous heat exposure in male infertility. Several occupational and environmental exposures and toxins have known or suspected deleterious actions to male reproductive function. The main objective of this study was to determine the frequency of occupational categories of men who attended an infertility clinic, and to evaluate the differences in the semen quality parameters among occupational categories. Materials and Methods: This cross-sectional study was conducted on 1382 males who were referred to the Royan Institute for treatment of infertility in order to evaluate the effects of certain occupations on infertility. The participants were divided into several categories according to their occupations and evaluated by means of a questionnaire for duration of infertility, BMI, sperm count, percentage of normal sperm morphology and percentages of sperm with class A and class B motilities. Descriptive statistics, analysis of variance, and correlations were conducted using SPSS 16.0 for Windows. Results: The means and standard errors of age, infertility duration and BMI of the participants were 33.89± 5.95 years, 6.23 ± 0.14 years and 26.06 ± 5.04, respectively. In this research , 47.4% of participants reported that they had a stressful working environment . Exposure to occupational physical hazards including heat, vibration, ionizing radiation and non-ionizing radiation were reported in 42.8%(n=498), 17.6% (n=205), 0.3% (n=4) and 39.1%(n=455) of the participants, respectively.The highest and lowest mean percentages of sperm with class B motility were seen in the Electronics group (25.94± 2.5) and the Transportation group (20.26 ± 1.07). Drivers are thought to be at greater risk of infertility because long periods of sitting can increase testicular heat, as the testicles are insulated by the thighs whilst a man is seated. Our findings in agreement with a number of other researches. Conclusion: Our findings support the results of previous studies regarding the association between occupation and sperm motility, particularly in the transportation category in which sedentary work is a common hazard. Further research is necessary to evaluate the observed associations in this study.