As I understand it, in a vasectomy, the vas deferens is cut and sealed, preventing the sperm from leaving the testicles. but the testicles don’t “know” that the vas deferens has been severed, so don’t they continue to release sperm during an orgasm? Is it somehow broken down? And where does it go? And if the guy is having an orgasm daily, can the body accommodate that much “extra” sperm?
The sperm is simply reabsorbed by the body, broken down into component molecules and recycled into new cells or (at the molecular level) excreted in the urine or feces. Same as any cell that dies a natural cell death, or any foreign microbe that gets into the body by way of a cut or puncture.
Sperm is not just manufactured and released at time of orgasm, although semen is. Your semen production is not affected since that is produced by your prostate. Sperm are generated constantly – a vasectomy severs the link to the storage area.
But where does the sperm go, to be reabsorbed, or does that happen in the testicles?
It gets broken down in the vas deferens and testicles where it’s stuck. There are huge (relatively speaking) white blood cells called “macrophages” that live in all our tissues and are essentially the garbage trucks of the body. They “eat” dead cells or invaders by engulfing them, and then use enzymes to digest, or break down, what they’ve eaten.
Remember that sperm is a small component, volume wise, of semen. You don’t make enough fast enough to cause any problems. By the time you’ve got today’s store made, yesterday’s is already breaking down.
Really, it’s no different than what happens to sperm of celibate men. It doesn’t leave the testes through ejaculation, so the body sends out its macrophages to clean things up.
What I recall from the explanation I got (15+ years ago) is that the tubes are not sealed closed, merely cut and separated. The semen spill out into your testicles, where it is reabsorbed through some mysterious process that wasn’t explained clearly.
Though they also to me that my body’s immune system would learn to treat the semen like some foreign cells and attack them – which is apparently one reason why there is a pretty high failure rate of reversing vasectomies. Even with all the plumbing reattached, the semen becomes a target and doesn’t survive to get into the ejaculate.
Just to make sure it’s a clear point, after the vasectomy, you still ejaculate, with no obvious difference from how it was before. It’s just now the ejaculate has no sperm cells in it.
Another point I learned when I had mine done about ten years ago, is that your body builds up cells to fight the sperm cells, so after a few years, even if you get the vas deferens re-attached, your fertility has gone way down because your body is now good at destroying sperm cells.
Point of correction: the sperm cells spill out into your scrotum. However, I don’t think they just leave the open-ended tubes floating around, because some sperm would still find their way across. Mine were sealed with little metal clamps.
From the brief burning flesh smell that occurred near the end of my vasectomy I believe mine were, uhh, heat-sealed. I was under a local anesthetic, didn’t feel a thing - but I do recall being a bit concerned at the time. That was roughly twenty years ago.
Yeah, in my case with a device that looked like a soldering iron.
I didn’t realize he was going to make two incisions, and screamed like a girl when the second needle went it in. I thought he was cutting without waiting for the anesthetic to begin working. 
Wouldn’t this also apply to men who are celibate for a long time? I’d think that it even refers to men who aren’t totally celibate, but just that they rarely have sex or masturbate.
If the logic is that an over-abundance of un-ejaculated sperm “trains” the body to get good at re-absorbing them, wouldn’t we have heard that celibacy affects fertility? If you know of such statistics, please share.
I’ve heard that celibate men almost never father children.
Greatest Exchange Ever.
What I *meant *was:
—> Wouldn’t we have heard that men who are celibate for a long time, and then stop being celibate, tend to be much less fertile than average? (An example of this would be a person who married late in life, and who follows his religion’s or culture’s avoidance of premarital sex and masturbation.)
:dubious: Was it really that hard to figure out?
[Foghorn Leghorn] It was a JOKE, son! A JOKE! [/Foghorn Leghorn]
I read about this many years ago and don’t know if it was ever commercially available, but there used to be a small implantable valve that could be stitched into the vas. It was for indecisive people like me who can’t pick a fucking side. Gives new meaning to the concept of bodily “plumbing”. At this point in my life though it just isn’t worth bothering. 
Yeah, that was offered to me in the 1980s, but kids REALLY cramp my style.
And what was it, a tiny stop cock with itsy bitsy hose clamps?
As long as sperm are migrating along the vas from the testicles to the prostate (the normal state of affairs regardless of orgasm) there is no requirement for testicular macrophages to destroy sperm (apart from some baseline level of non-motile sperm cells). So celibate men do not build up a response to their own sperm. Their sperm is removed along with prostatic fluid (either by prostatic reabsorption or nocturnal ejaculation) which does not trigger the same immune system response.
It should also be noted that this immune response in men with vasectomies is not a guarantee of sterility, and men can become fertile many years after a vasectomy if the severed vas rejoins (or a surgical reversal takes place).
Si
Wait wait wait wait wait.
Wait.
After you’ve had a vasectomy you still ejaculate? As in, not a dry shot but you’re actually ejaculating fluid?
I didn’t know that.
Fighting Ignorance …
It’s why we are here.
There is no observable difference between a pre and post vasectomy ejaculation, unless you use a microscope. And while there are no sperm cells in the ejaculate, there are almost certainly enough other DNA containing cells for a DNA id.
Si