Effect of vasectomy on thyroid function.

Long-Evans rats vasectomized unilaterally or bilaterally at 2 months of age showed marked reductions in weight of testes, seminal vesicles and prostate glands 2 and 12 months post-vasectomy. Thyroid weight, thyroid 131I uptake, serum PB131I, circulating levels of serum T4 and chromatographic analysis of thyroid hydrolysates revealed no alterations due to vasectomy. These findings indicate that vasectomy, unilateral or bilateral, and whether of 2 or 12 months duration, did not exert an effect on thyroid function.