METHODOLOGICAL ASPECTS OF SPERM MORPHOLOGY EVALUATION - COMPARISON BETWEEN STRICT AND LIBERAL CRITERIA

Objective: To compare the methodological accuracy of different sperm m orphology criteria. Setting: A multicenter study including 10 laborato ries with high expertise in semen analysis. Patients: Semen preparatio ns of subfertile men with a variable degree of teratozoospermia and of fertile semen donors. Interventions: Detailed assessment of sperm mor phology on 10 air-dried semen smears, of which 3 originated from the s ame ejaculate. Results: The average coefficient of variation calculate d on the three smears of the same ejaculate was higher when strict cri teria for morphological normality were used and borderline cells were classified as abnormal than when criteria of abnormality were applied and borderline cells were considered normal. The correspondence betwee n individual centers mutually and of each center with the average resu lt of all centers was better when the latter approach was taken. The p erformance of two computer-assisted systems was intermediate between t hat of the two approaches, whereas one system gave unreliable results. Conclusions: Strict criteria for normality of sperm morphology, with borderline cells considered abnormal, gives results that are less repr oducible and less accurate than the approach that classifies sperm as abnormal, with borderline cells considered normal.