RESUMO
BACKGROUND: Fatty acids composition of the spermatozoa may be an important determinant of sperm quality and fertility. This study aimed to evaluate the fatty acids profile of seminal plasma and membrane spermatozoa and to study the association between fatty acids and sperm properties. METHODS: Semen samples were collected by masturbation from 45 middle-aged men consulting for infertile couples. Semen cytomorphological analysis was performed after liquefaction. Semen was classified as normal or abnormal according to World Health Organization criteria 2010. Plasma seminal and spermatozoa membrane fatty acids composition were analyzed by capillary gas chromatography. RESULTS: Docosahexaenoic acid level was decreased while oleic acid level and n-6:n-3 ratio were increased in spermatozoa membrane in men with abnormal sperm. However, no variation in seminal plasma fatty acid composition was found between men with normal and abnormal sperms. Spermatozoa docosahexaenoic acid was positively correlated with sperm concentration and progressive motility and inversely related to atypical spermatozoa number, while oleic acid showed the inverse correlations. CONCLUSIONS: Altered fatty acids composition in the spermatozoa membrane, especially a decreased docosahexaenoic acid content, is associated with poor sperm quality. Although a causal association could not be established, intervention that recovers normal spermatozoa fatty acid composition could contribute to improved sperm quality.
