Your husband would most likely benefit from seeing his doctor immediately. The blood that he ejaculates during sex may originate from the genital system (prostate gland, seminal vesicles, ejaculatory ducts, vas deferens, epididymis or testicles). Several physical exams (rectal exam, for example), laboratory analyses (sperm, blood and urine analyses, PSA), imaging tests (ultrasound, CT-scan) and other procedures (endoscopic cystoscopia) can be requested and performed in order to diagnose and identify the cause for ejaculating blood.