Sperm Motility

Sperm motility constitutes a major parameter of the basic semen analysis. Following the new WHO manual sixth edition, it is re-evaluated to provide insight on its role as a fundamental aspect of sperm fertility potential. Sperm motility may act as a strong marker of male reproductive function, mirroring detrimental effects of various conditions, in conjunction with sperm vitality. The categorization of four motility types and other indices, such as the total progressive sperm count, have also been associated with reproductive outcomes. Most of the etiological factors of motility defects still remain unknown. Its levels may be influenced by abstinence, hyperviscosity, agglutination, lifestyle habits, chemical pesticides, air pollution, drugs, heat, infection, and psychological stress. Mutations in genes controlling flagellar structure, energy supply, signaling pathways, annulus, and sperm mitochondria, may also be implicated. Additional investigations, e.g., oxidative stress evaluation, genetic, immunological, and microbiological examinations are suggested to further elucidate this issue. The first line management of sperm motility discrepancies includes lifestyle modifications, varicocele repair, and antioxidant supplementation. Furthermore, the application of assisted reproductive methods is adopted according to specific thresholds, depending on the total number of progressively motile spermatozoa, with or without in vitro enhancement by chemical substances.