A prosthetic vas deferens.

36 dogs previously vasectomized were implanted with prosthetic devices designed to aid in developing a method of reversibly occluding the flow of spermatozoa in the vas deferens. Short-term effects of the sperm in contact with prosthetic materials and long-term effects associated with reactions which result from changes over time were studied. The device was composed of silicone rubber pilot tubes which were flexible and could conform to the vas movements. 3 lengths of the device were tried: 1.55 2 and 4.3 cm. The duration of implants studied was from 0 to 12 months. All 6 dogs had sperm restored to their semen. Results indicate that sperm motility was poorly restored by the prosthetic devices. However sperm motility was affected to a greater degree by aspermic duration than by length of sperm transport path. Sperm counts were restored only to about 15% of preimplant levels. Varying lengths were unable to improve this result. The potential application of this device to the human male is suggested.