The other day i was able to assist in a very sensitive procedure, a vasectomy. For those who don't know what it entails i'll tell you.

First step is to find the vas deferens on both sides of the scrotum, make an incision and cleaning them off from their blood supply. because you don't want to bleed into the scrotum it would cause a good deal of pain and brusing. Next you clamp of two parts of the vasdeferens and then snip off the segment in between, we went with a size of 1.5cm, but as you'll see there is some debate as to how much you really need to take. Then lastly you tie off both ends that are left on each side, cauterize them and then tuck them back into the scrotum then suture up the scrotum. The whole procedure takes a little over an hour.

Now cutting the vas deferens and tying off the ends, as well as cauterizing them, you think would be enough to keep the two ends of the vas deferens apart. However, there have been a few report cases of the ends reconnecting, yeah reconnecting. Obviously this poses a problem since you wouldn't have undergone the procedure if you didn't expect it to be a permenant fix. Depending on the article as much as 2% of men undergoing vasectomy could see a failure. The methods for determing failure were based on semen analysis 2-3 months after the procedure, a time legth that was believed to be long enough for the residual sperm to die, or have been removed. The most obvious failure type was not waiting long enough after the vasectomy to resume having sex.

The following articles show some reasons touted for failures of the vasectomy and particularly recanulization. While recanulization isn't the only method of vasectomy failure i thought that was an interesting one.

Some of the ideas believed to be the cause of recanulization are that the size of the vas deferens removed was to small. There are some conflicting studies on this a study out of quebec proved it had no association, while another study stated that a specific   amount of vas deferens should be removed. Another idea was that it had to due with the level of experience that the surgeon perfoming the procedure had. This also was proven not have a strong association. The most interesting reason for recanulization that i read had to do with the sperm forming a granuloma and connecting the two ends of the vas deferens back together. This is quite amazing to think that the sperm themselves build a bridge and actually reconnect their way out.  As you might guess the ones that were most dissapointed by the recanulization were the patients wives, because the most common way to realize that the vasectomy had failed, was.. pregnancy.