NSV does not affect erection or ejaculation. Ejaculatory fluid, semen, is made in the prostate and the seminal vesicles, which are not cut during vasectomy. The amount of fluid that comes out of the testicle with sperm is less than 1% of the overall ejaculated volume. The muscle contractions that force fluid out during ejaculation come from the pelvis and are not affected by NSV.
The testicles make both sperm and testosterone. The testicle makes testosterone and transports it through the blood stream, not the vas deferens. Testosterone levels do not go down as a result of permanent sterilization.
There is no established relationship between NSV and prostate cancer. Prostate cancer is primarily identified through screening. A man who undergoes vasectomy is more likely to get screened for prostate cancer than a man who doesn’t.
Vasectomy does not decrease semen production. Men continue to make semen in the same way as before the procedure.