J P Ramírez | Search PubMed

PubMed2005

External quality control program for semen analysis: Spanish experience.

PURPOSE: Results from an external quality control programme for semen analysis carried out in Spain are analysed. METHODS: Quality control materials were distributed and the following seminal parameters were determined: concentration, total motility, progressive motility, rapid progressive motility, morphology and sperm vitality. The between-laboratories coefficients of variation were assessed on different types of quality control material. RESULTS: The majority of participating laboratories utilised manual versus computer-assisted semen analysis methods. Some between-laboratories coefficients of variation ranges were: 20.8-33.8% for concentration (semen pool suspension); 13.9-19.2% for total motility (videotapes); 54.2-70.2% for sperm morphology (strict criteria using stained smears); and 9.8-41.1% for sperm vitality (stained smears). There was an inverse relation between mean percentage of sperm and coefficients of variation between laboratories for sperm motility, morphology and vitality. CONCLUSIONS: These data highlight the urgent need for improvement in the overall quality of andrology testing.

Clinical Laboratory Techniques↗

PubMed2003

Biological variation of seminal parameters in healthy subjects.

BACKGROUND: A study was undertaken to assess the components of biological variation of seminal parameters in healthy subjects. METHODS: Twenty donor candidates were included in a 10-week follow-up study. Within- and between-subject biological variation, indices of individuality and heterogeneity, coefficient of reliability, critical differences, analytical goals and the lowest value observed with a <5% probability of having a true value less than the World Health Organization (1999) reference value were estimated for the following seminal parameters: concentration, total motility (WHO grades a + b + c), progressive motility (grades a + b), rapid progressive motility (grade a), sperm morphology and vitality. All analysis was performed by a single technician according to WHO 1999 guidelines for routine semen analysis. Analytical variation was assessed on different types of quality control material (frozen straws, sperm suspension, videotape, and slides) and at different (low, medium, high) quality levels. RESULTS: The analytical variation observed depended on the quality control material used and the level of semen quality. Concentration was the semen parameter with highest within- and between-subject variation, and vitality the lowest. Indices of individuality were all <0.7, and coefficients of reliability were high (0.68-0.84). The critical difference for sequential values significant at P < 0.05 for vitality, progressive motility and morphology (34.4, 49.2 and 58.0% respectively) were lower than for concentration (77.8%). CONCLUSIONS: The study results showed that conventional reference values for seminal parameters have little diagnostic value because of their marked individuality, though seminal parameters can be useful for assessing differences in an individual's serial results, in particular of progressive motility, morphology and vitality.

Adult↗