The long-term influence of vasectomy on prostatic volume and morphology in man

Abstract

During the past two decades several papers have described the changes in prostatic secretory capacity following vasectomy. Based upon results indicating a reduction of secretory function, it was suggested that even prostatic size and the incidence of benign prostatic hyperplasia (BPH) might be altered after the operation. In this study, which included 56 males who had been vasectomized 8 years previously and 56 age-matched control persons, transrectal ultrasonic scanning of the prostate was used for exact measurements of the prostatic volume and for the investigation of intraprostatic echo pattern. The total prostatic volume, the volume of the periurethral gland, and the volume of the peripheral zone were not influenced by the vasectomy; nor was the growth rate of these zones affected. In the vasectomy group, the frequency of adenomatous prostates was 19.6%, whereas 30.3% of prostates in the control group had ultrasonic signs of BPH. However, this is not a statistically significant difference. Subdividing the material according to age did not reveal altered BPH frequency in any age group when vasectomized and controls were compared.

PIP: 56 males who had been vasectomized 8 years previously and 56 age-matched control persons participated in this study designed to investigate the long-term influence of vasectomy on prostatic volume and morphology in man. All patients were vasectomized under local analgesia on an outpatient basis using bilateral scrotal incisions and resection of 1-2 cm of the vas deferens. The nonvasectomized men in the control group were selected at random. Transrectal ultrasonic scanning of the prostate was performed after 3 days of sexual abstinence. The patient/control person emptied his bladder by a normal voiding procedure immediately before the scanning, which then was performed with the person in the left lateral position. All prostates were scanned in the radial plane. A careful medical history was taken in all cases. Special attention was given to urogenital disorders and voiding symptoms. The 2 groups were comparable with respect to medical history, previous and current diseases and medication, tobacco and alcohol consumption, height, weight, and surface area. In the vasectomy group, 11 of 56 (19.6%) had ultrasonic signs of developing or established adenomas; of the control group, 17 of 56 (30.3%) prostates were adenomatous. The difference was not statistically significant. No statistically significant differences were found between the 2 groups when normal and adenomatous prostates were evaluated independently, with 1 exception. In vasectomized men with normal prostatic echopattern, the relative volume of the periurethral gland was found to be slightly but significantly larger then the corresponding value in controls. In each group, adenomatous prostates presented with significantly larger total volumes, larger volumes of the periurethral gland, and larger relative volumes of the periurethral gland. No change was found in the peripheral volume when adenomas developed. No statistically significant differences between the volumes were found in any age group when patients and controls were compared.