Brief Answer:
fishy smell of semen could be associated with infection(bacterial or yeast)

Detailed Answer:
Hi,
Welcome to health care magic,

Semen might have different different smells normally or when there is some sort of infection.

Semen contains ammonia and other sterile-smelling alkaloids and this is the reason why it smells like your fishy or cleanser.

Foul or fishy smells of semen could be associated with infections of the prostrate gland or other organs of the male reproductive system.

If the smell is accompanied with a change in colour of the ejaculate to red, brown, yellow or green, your boy friend might have an infection.

So,it would be advisable to consult a physician and get a diagnosis done with clinical examination and relevant investigation like routine blood,ESR,semen examination or pelvic ultrasound.

Hope this information will be useful,

Regards,
Dr.Sandip

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