An acute oral administration of Sildenafil in asthenozoospermic patients improves sperm motility after density gradient centrifugation.

Objective: Investigate the possible effect of an acute sildenafil dose in asthenozoospermic patients. Methods: We ran this experimental, descriptive, prospective and non-blinded study in 32 patients diagnosed with asthenozoospermia according to the WHO criteria, after two consecutive semen analyses (samples 1 and 2), and we asked them to provide a new semen sample two weeks after the initial exams (sample 3). One hour prior to the semen collection, we gave the patients 100mg oral sildenafil. Samples 2 and 3 were allowed to liquefy and density gradients centrifugation was performed. We assessed sperm motility by Computer-assisted sperm analysis (CASA). Results: There were no significant differences between the samples obtained before (sample2) or after sildenafil administration (sample3). However, a single oral 100 mg sildenafil dose in asthenozoospermic patients increase the percentage of motile sperm recovered after density gradient centrifugation. Conclusions: An acute administration of sildenafil enhances sperm recovery after density gradient centrifugation in asthenozoospermic patients, and it may produce more available mobile sperm to perform intra uterine insemination or to improve the chances of success in this procedure. This approach may be used as an alternative strategy in assisted reproductive programs. Sildenafil was well tolerated and no patient was withdrawn from the study due to adverse events attributed to sildenafil.