Proteolytic enzymes stimulate human spermatozoal motility and in vitro hamster egg penetration.

Addition of chymotrypsin or trypsin decreased the viscosity of highly viscous semen of subfertile patients. Besides that spermatozoal motility (in 50-80% of the case) and in vitro fertilizing ability was measured with zona-free hamster ova (in 35% of the cases) were increased of both normal and highly viscous semen.