Persistent effects of pentoxifylline on human sperm motility, after drug removal, in normozoospermic and asthenozoospermic individuals.

The aim of the study was to compare the in vitro effect of pentoxifylline on human sperm motility when added prior to sperm selection and the persistence of the response after drug removal in normo- and asthenozoospermic individuals. The sperm samples were obtained from 22 men who were repeatedly asthenozoospermic or normozoospermic. Sperm movement was measured using computer-assisted semen analysis over 180 min. Percentage motility and progressive motility were increased in both normo- and asthenozoospermic samples (P < 0.05). Curvilinear velocity, amplitude of lateral head displacement and beat-cross frequency were increased in both groups (P < 0.05). Straight-line velocity was increased significantly in the normozoospermic group only. In both normo- and asthenozoospermic individuals pentoxifylline appeared to enhance sperm motility for at least 180 min after drug removal. This should prevent any potentially toxic effects of the drug on oocytes if it is used to enhance sperm motility during in vitro fertilization.