Vasectomy: Immunologic Effects in Rhesus Monkeys and Men

Abstract

In order to determine: 1) if antibodies against spermatozoa are formed in vasectomized males and 2) the long-range physiological effects of vasectomy spermatozoa and serum from 30 vasectomized men and 26 vasectomized rhesus monkeys were tested. The average spermagglutinin titer increased over time in the human samples while decreasing and remaining low in most of the monkey samples. Sperm-immobilizing antibodies were detected in some rhesus monkeys within 2 weeks after vasectomy. Ammonium sulfate precipitation showed spermagglutinating antibody in the immunoglobulin fraction. In rhesus monkeys aggluntination was not the result of secretion from the accessory sex glands since both ejaculated and epididymal spermatozoa agglutinated in the presence of vasectomized monkey serum; hence the antigens recognized by the spermagglutinating antibody must have been present before accessory fluids were added. In investigating the long-range effects of vasectomy monkeys who had been vasectomized for 12 months did not differ from sham-vasectomized animals in white blood counts glucose levels urea nitrogen creatinine total protein globulins acid phosphatase serum glutamic pyruvic transaminase and insulin. Animals vasectomized for 4-8 years showed no significant difference in urea nitrogen creatinine albumin gamma globulin or the A/G ratio when compared with their own earlier blood values or appropriate controls. Urine from these long-vasectomized animals with sperm-agglutinin titers showed no abnormalities. Based on this data vasectomy appears to be a safe method of sterilization that causes no deleterious effects.