Anatomy: why is it hard for a man to pee shortly after ejaculation?

Subject line contains the basic question: shortly after orgasm/ejaculation, it’s usually a few minutes before I can pass urine. What’s happening to produce this phenomenon?

The bladder neck muscles autonomically contract during ejaculation to prevent semen from going into the bladder instead of out the urethra. It just take a little while to relax.


You said “hard”.

A useful adapation, I suppose, to ensure that those precious bodily fluids go where they’re supposed to. But why do the muscles remain contracted for some time post-climax?

Sounds right. Does anything similar happen to a woman after orgasm? I know there is no semen to justify it, but aren’t male and female muscles around that area similar?

Why not? It’s not as if anyone ever died from that.

But if the semen doesn’t go ‘out’ it can’t make babies. Path of least resistance and all that.

Thus, post-ejaculation urine clamp is selectively neutral, as it occurs after the male has bred. Now, if PEUC causes men to die before their children reach breeding age themselves, it might be selected against. But if, as I said, no one has ever died for not being able to take a leak for a few minutes after ejaculation, it cannot be selected against.

“Bred”? You’re a veterinarian, right?

This is what I was wondering - does this phenomenon serve an evolutionarily useful purpose, or is it just a harmless artifact of the way the reproductive system happened to evolve?

Before this gets up to full speed, did DrFidelius just invent the term “post-ejaculation urine clamp?” It sounds doctory, and even has an abbreviation.

Even if (because?) DrFidelius is a vet.
ETA: I need to know who to give credit to the next time the situation arises (npi) and I tell my wife why I’m getting up (npi). I’m conscientious that way.

What happens after ejaculation is kinda irrelevant.

As far as I know, I did just make that up on the fly. Come to think of it, it sounds like one of those uncomfortable devices for sale at Ilsa’s Leather Boutique.

Is that where the urine clamp is?

For “why” in the evolutionary sense, why not? For “why” in the mechanics sense, you’d have to ask a neuroscientist. It’s a spinal reflex, I suspect it would have something to do with neurotransmitter re-uptake time.

During my online research, I have observed a number of women having presumably real orgasms that result in the involuntary emission of what is obviously urine. Based on that I would assume the answer is no.

IIRC, the real premise was to prevent the flow of Urine once excited, as urine can kill sperm (due to acidity?) - thats the purpose of ‘pre-ejaculate’ (clean the pipes), etc.

So, it follows that keeping it clamped afterwards is just an extension of that -

I was reminded of a capo.

RE women:

For me, and I hear the same thing from friends, I can pee right after but I can’t always walk properly. So there is some muscular funniness, but not in the bladder/urethra department.


I thought it was hard to pee after ejaculation because you were asleep by then. :slight_smile: