During a vasectomy, the tube which carries sperm from the testicles to the urethra (the tube in the penis) is cut. Once this happens, sperm can’t get into the semen or out of the body. But where do they go?
Sperm are still produced by the man’s testicles, but they are absorbed back into the body in a way that is harmless. The lining of the epididymis, the coiled tube behind the testes, absorbs most of the sperm, similar to if the man simply couldn’t have sex for a long time.
The testicles will continue to produce the male hormone testosterone, and a man’s sex drive, sensation and ability to have an erection won’t be affected – the only difference is that there is no sperm in the semen.
It’s worth saying that this doesn’t happen immediately – it can take several weeks to clear the sperm, because some stay in the tubes after the procedure. For most men, sperm will be cleared by around 12 weeks after the procedure, but contraception needs to be used until the semen is tested and found to be clear.
Read more:
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- What happens if a man takes a contraceptive pill?
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