“Blood in the semen is most commonly a result of a prostate gland biopsy. More than 80% of men who undergo a prostate biopsy may have some blood in their semen that persists for three to four weeks. Likewise, vasectomy can lead to bloody semen for about one week after the procedure.”
There are a lot of reasons for having blood in your semen. Hematospermia can result from non-threatening causes such as a recent vasectomy or a prostate biopsy. However, in the absence of a recent vasectomy or prostate biopsy, hamatospermia can be a sign of other problems in the body: benign/malignant tumors, cysts or hemorrhages in seminal vesicles, stones in the prostate or seminal vesicle, prostate or urethra inflammation or sexually transmitted infections along with many others.