Semen quality of smoking and non-smoking men in infertile couples in a Swedish population.

A study of semen quality, using conventional semen analysis, was undertaken. 186 male smokers were compared with 164 non-smoking men undergoing infertility investigation. The cigarette smokers were subdivided into three groups according to the number of cigarettes they smoked: less than 10 (n = 27), 10-19 (n = 84) and greater than 19 cigarettes per day (n = 75).