The clinical value of conventional semen analysis
The object of this thesis was to determine the independent predictive value of semen parameters obtained from the conventional analysis of semen by the methods advocated by the World Health Organisation in 1987, and of the descriptive semen categories also advocated by the World Health Organisation in 1987. The laboratory error in assessing sperm motility, density and morphology was quantified, and minimised by examining the predictive value of semen analyses performed by one technician. It was determined whether it is important to employ stringent criteria for recruiting fertile controls, by comparing semen parameters obtained from 'fertile' men who were recruited by two different methods. The relationship between demographic and clinical female factors and the cumulative conception rate was studied. The relationship between semen parameters and fertility was studied by two different methods. Firstly 'fertile' controls were compared to men who had attended an infertility clinic who were grouped by details of their partners. Secondly the relationship between semen parameters and the cumulative conception rate was studied after having considered known female factors. The relationship between information obtained from the history and physical examination of the male partner and the cumulative conception rate was studied, and it was determined whether semen analysis furnished predictive information independent of these features. This study also attempted to determine how many semen samples should be examined for optimum predictive value.