This experiment was planned to answer the question of how the elimination of ipsilateral spermatogenetic material, which is necessary for contralateral testicular damage caused by an autoimmune response, affects contralateral testicular blood flow and fertility potential in unilateral spermatic cord torsion (USCT). Thirty-four male and 68 female adult albino rats were divided into three groups. Group 1 rats underwent a control operation, group 2 rats underwent subepididymal orchiectomy to eliminate spermatogenetic material, and group 3 rats underwent USCT after subepididymal orchiectomy. Testicular blood flows of the rats were measured by Xe-133 clearance technique. Additionally, to determine fertility potential, each male rat was housed with two female rats. Numbers of impregnated and delivered rats were recorded. Both mean testicular blood flow and fecundity of group 3 were significantly lower than those of groups 1 and 2. When compared with groups 1 and 2, fertility and mean number of the impregnated rats of group 3 were lower but the differences were not significant. These findings suggest that absence of spermatogenetic material in USCT reduces contralateral blood flow and fertility potential. Therefore, contralateral testicular damage originating from blood flow alterations rather than autoimmune mechanism should be considered to explain fertility problems encountered following USCT.