This report describes the procedure for percutaneous injection of silicone to form plugs in the vas deferens. The injection of 0.1-0.16 ml Chinese-made silicone into 14 men achieved occlusion of a 1-cm length of the vas. Sperm concentrations declined within 1 month of the operation and azoospermia was achieved in all men by 9 months.
PIP: In China, 14 29-36 year old men underwent percutaneous injection of medical-grade silicone into the vas deferens at the Shanxi Provincial People's Hospital in Taiyuan. They collected semen samples 2 weeks after the operation and every month thereafter. The men and their partners used their usual contraceptive method until there were 3 consecutive azoospermic samples. No postoperative medical problems occurred. Neither complications nor discomfort existed in the scrotal region. The vas near the plugs did not exhibit any signs of tenderness or enlargement. The operation did not affect their libido. By 1 month after the operation, sperm counts had already begun to fall (76.9-58.8 x 1 million ml-1). By 5 months, 3 men had achieved azoospermia and the remaining 11 men had severe oligospermia. All the men had achieved azoospermia by 9 months. Sperm motility fell in concert with the fall in sperm concentration, but 11-44% of the residual spermatozoa at 5-6 months was greater than that of surgical vasectomy. Apparently, the vas adapted to the plug causing full occlusion between 6 and 9 months. The silicone plug method was developed to keep the vas deferens intact to facilitate reversal. Further research is needed to understand the ability of the plug to adapt.