The ability of pentoxifylline and 2-deoxyadenosine to stimulate sperm motility and motion characteristics was assessed in unprocessed and processed (Percoll-separated) cryopreserved specimens. Specimens from 12 healthy volunteers were obtained, and the motion characteristics were analyzed; half the sample was immediately cryopreserved and the other was washed using the Percoll gradient technique. To study stimulation, samples were thawed and divided into four aliquots: One was used as a control, and the others were incubated with 2.5 mM 2-deoxyadenosine, 2.5 mM pentoxifylline, or 5.0 mM pentoxifylline for 60 min. Sperm characteristics were analyzed on a sperm motion analyzer at 0 and 60 min incubation. In both unprocessed and processed samples, percentage motility improved significantly after stimulation with 2-deoxyadenosine or pentoxifylline (p = .003 or p = .0002, respectively); other characteristics improved to varying extent after 2-deoxyadenosine or pentoxifylline stimulation. Comparison after stimulation revealed that sperm motion characteristics in the unprocessed specimen were similar to sperm motion characteristics in the processed group.