External quality assessment for semen analysis and sperm antibody detection: results of a pilot scheme.

The need for quality assurance in the seminology laboratory is clear, as the techniques of semen analysis and sperm antibody detection are just as susceptible to variation as any other routine pathology test. Semen samples were distributed to 20 laboratories on six occasions, four samples per distribution, for sperm concentration and morphology assessment under routine conditions, together with an equal number of serum samples for sperm antibody detection. The semen analysis results showed a wide range of values for any given sample, which did not seem to be related to the methodology used. However, this variation appears to be related to the presence of persistent errors, as most laboratories showed reasonable between-assay and within-assay variation. Detection of sperm antibodies by the tray agglutination, gelatin agglutination or indirect immunobead test showed a consistent discrimination between the intended positive and intended negative samples. However, the use of fluorescent microscopy was unable to do this. This study has shown the feasibility of operating external quality assessment schemes for semen analysis and sperm antibody detection. These schemes provide the opportunity for individual laboratories to fully evaluate their own methods against those of others and to determine the stages at which any errors occur. An increased number of participants will ultimately enable a systematic comparison of different methods.