Sperm are produced by the testicles, which are located in the scrotum. Once produced, the sperm exit the testicle through the epididymis where they mature. The tail of the epididymis drains into the vas deferens which is incorporated within the spermatic cord and travels through the inguinal region into the retroperitoneal space.

The vas eventually empties into the ejaculatory duct within the prostate, along with the seminal vesicles. At orgasm, semen is produced and is made up of sperm and fluid from the prostate and seminal vesicles. Volume wise, the sperm represent a small portion of the seminal fluid, and after vasectomy there is no noticeable decrease in the volume of the ejaculation. Sperm are still produced in the testicle after vasectomy, however they can no longer pass through the vas deferens since it has been divided with vasectomy. The sperm die within the testicle and are reabsorbed.