Predictive value of sperm hyperactivation measurements based on the dilution effect method in clinical in vitro fertilization.

Sperm hyperactivation motility characterized by wide oscillatory movements of the sperm head, nonlinear directions, and rapid motility with occasional star-shaped pattern of movement was measured during routine semen analyses prior to an in vitro fertilization procedure. The method consisted of diluting liquefied semen 1:20 with Ham's F-10 supplemented with processed human cord sera followed by incubation at 37 degrees C for 30 minutes. At the end of the incubation period, aliquots of semen samples were evaluated by phase contrast microscopy for sperm hyperactivation. The results indicated that (1) sperm samples exhibiting 15% or more hyperactive motility were associated with a significantly higher percent fertilization of oocytes during the IVF procedure; (2) sperm hyperactive motility was correlated to sperm fertilizability during IVF treatment cycles.