After a vasectomy, the tube running from testes to the penis is no longer connected. The testes are still very much alive and functioning; Leydig cells continue to produce testosterone and hormones, which continue to be absorbed into blood. The only difference is that the path that sperm travels is interrupted. Sperm that is produced is broken down by the body. The epididymis’s membranes absorb the liquid created, while solids substances are broken down by macrophages and absorbed into the bloodstream. With the increase of stagnant sperm, the membranes of the epididymis increase in size to absorb more liquid. The immune system increases the amount of macrophages to handle an increase of solid waste.
No scalpel vasectomies are, for all intents and purposes, permanent. Reversals are costly, have a considerably lower success rate, and often does not restore the sperm count and/or motility to pre-vasectomy levels.
Confirmed, properly performed no scalpel vasectomies ensure life-long sterility with almost no chance of making a woman pregnant . It does not, however, prevent the transmission of STDs.