What a Vasectomy Does and Does Not Do
In a vasectomy, the surgeon cuts and ties off the ends of the vas deferens. This prevents sperm from mixing with the seminal fluid. Although the testes will continue to produce sperm, they can no longer pass through the vas deferens. Instead, they die and are absorbed into the body.
Because semen consists of about 95% seminal fluid, there is virtually no discernible difference in the ejaculate. Similarly, because the testes continue to produce the male hormone testosterone, which is absorbed into the bloodstream, the procedure also has no effect on a man’s sex drive.
The urologist first numbs the scrotum and vas deferens with a local anesthetic. Then, one or two incisions about half a centimeter long are made on each side of the scrotum. The vas deferens are located, a one-centimeter section is removed and the upper and lower ends are tied with suture or a clip is placed. Sometimes stitches are used to close the incision in the scrotum. If ties are used around the vas deferens, they usually dissolve over a period of 4 to 6 weeks.