318. Long-term effect of vasectomy on endocrine function in man

Abstract

The long-term effect of one of the most extensively practiced antifertility procedures vasectomy on endocrine function in man has not been determined. We measured testosterone (T) and follicle stimulating hormone (FSH) by radioimmunoassay and testosterone binding (TB) by equilibrium dialysis in the plasma of 81 subjects from India of whom 12 were vasectomized for a period up to 5 years 20 for up to 4 years 21 for up to 3 years and 28 for a period between 1-2 years. The concentrations found in the different groups were for T 596 + or - 157 594 + or - 187 530 + or - 195 and 562 + or - 185 ng%; for FSH 14.63 + or - 5.74 13.74 + or - 6.09 15.74 + or - 8.14 and 17.44 + or - 9.85 mlU/ml; and for TB 93. 74 + or - 1.19 93.37 + or - 2.37 92.14 + or - 2.57 and 93.18 + or - 1.99% respectively. The mean values found in a control group of 16 normal males belonging to the same age group and the same geographical area were T = 582 + or - 158 ng% FSH = 15.09 + or - 8.74 M1U/ml and TB = 92.99 + or - 1.14%. Students t test between groups showed no significant difference between the control group and any of the other groups studied (p less than .001). These results show that vasectomy in man does not cause detectable abnormality in testosterone and FSH secretion and testosterone binding globulin synthesis even up to 5 years after operation. However since a large variation was observed in the parameters studied among the individuals within each group this investigation should be extended to study the concentration of these hormones in the same individuals before and after vasectomy. (FULL TEXT)