Hi, i did understand your concern. Hematospermia as the condition described by you can be quite distressing problem. However, interesting fact that it happens only while intercourse and not while you masterbate.. it raises the suspicion that it can be blood of your partner if its a single partner. so my advice would be to get herself evaluated by a gynecologist as well as you being evaluated by a urologist. It can be caused by many pathology such as infection, unwanted growth, inflammation and best investigation would be semen analysis and cystoscopy and urine analysis. ALso cialis can very rarely cause hematospermia as you are taking for it and you can review your medication with your doctor. I hope this helps. Let me know if you have any more questions or concerns. Wish you healthy and happy life ahead.