Sperm are male reproductive cells that are formed in the seminiferous tubules of the testes. Sperm travel through a lengthy duct system starting from the testes, through the epididymis, and then through long, narrow tubes called the left and right vas deferens. The sperm continue to move through the seminal vesicles, the prostate gland, and the bulbourethral gland, mixing with seminal fluid and forming the ejaculate called semen. During a vasectomy, the vas deferens are cut and tied off so that sperm cannot be ejaculated. Ejaculation still occurs normally; however, sperm are not a product of the ejaculate. Therefore, fertilization will not occur. Following a vasectomy, sperm are still produced, but are harmlessly absorbed by the body. There are several potential complications associated with this procedure that should be discussed with a doctor prior to surgery.