I found what looks like old blood in my sperm, what causes this and what can I do to correct this I am 61 years of age, I have not had any injuries to my groin area

Hematospermia . Hematospermia (blood in sperm) is most usually caused by a prostate infection or a small prostate calcification. Though is is a scary symptom, it is rarely attributable to cancer. Please make an appointment to see your physician to have an exam and more testing. Best wishes.