Brief Answer: Hi and welcome to XXXXXXX Detailed Answer: Thanks for the query. In most cases the cause of blood in seminal fluid is benign and this happens due to urinary infection, kidney stone, prostate enlargement or trauma. Sometimes, the exact cause cant be established at all. Of course,some more possible causes such as tumors are possible,but this is the last thing to think of. This is common in your age and most cases resolve on their own,especially if there is no some other symptom such as pain during urinating,urethral discharge, testicle pain, penis rash. If you have any of these or blood persists for more than 4 weeks, you should do basic urine analysis and urotract ultrasound to rule out infection and stones. Wish you good health. feel free to ask. Regards

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