I have a question: can a man ejaculate urine instead of semen during orgasm? What about ejaculating without being erect?
That would be two questions actually, but they are related. The male urogenital system is quite complex and fascinating—at least I think so. Although the urethra that passes through the penis is used for both urine and semen excretion, it cannot be used for both at the same time.
When a man becomes aroused, the pathway from the bladder to the urethra becomes increasingly closed off, preventing the flow of urine. Prior to ejaculation, it is impossible for a man to urinate. This is the common cause of men waking up with an erection and being unable to pee in the morning. However, the mechanisms for erection and ejaculation are not so closely tied together. Although -- in the usual scheme of things -- a man will be at least partially erect when he ejaculates, there is no physical reason he could not be flaccid. In fact, in men with various health conditions that prevent full erection this is often exactly what happens. They have all the same feelings of building sexual tension, followed by a release during orgasm, just without an erection.
And, to answer your second question: Yes, some men might be able to urinate very close to ejaculation (if they have little or no erection), but still not at the same time -- since erection and arousal both work to close off the pathway to the bladder. Hope that clears things up for you.
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