640 men with wives who had trouble getting pregnant (and ultimately did not get pregnant) were compared with 227 men with wives that were pregnant.
The study found that male technicians, financial analysts, senior executives, and IT managers and -teachers were at increased risk of being childless; in fact, this risk was 3 - 8 times higher than that of men with other occupations. Men working in service jobs and as office assistants had the lowest risk of becoming childless.
It was less surprising that the study showed that smokers had a threefold risk of being childless compared to non-smoking men.
The researchers themselves draw attention to the fact that their study is far too small for them to be able make any decicive conclusions and indicate possible causes such as a large workload, stress, and possibly exposure to electromagnetic radiation.
Reference:
Chia, Sin-Eng and Tay, Sun-Kuie. Occupational Risk for Male Infertility: A Case-Control Study of 218 Infertile and 227 Fertile Men. Journ of Occup and Enviom Med 2001;43:946-51.
