Every time I finish after sex (or self-stimulation) the end result comes out pink. What gives? -- Don, 25, Levittown, PA 

Pink semen is understandably alarming—though, fortunately, it is seldom serious.

Semen, of course, is normally milky white.  If it’s pink, that means blood is mixing with the semen.  The medical name for the condition is hematospermia.

The most common cause is an infection of the urethra, the prostate, or the seminal vesicles.  In these cases, the condition often goes away once the infection clears up (either naturally or with the help of antibiotics).  But pink semen could also be a sign of prostate cancer, so you should always see a doctor and get properly diagnosed.

Dr. Harry Fisch is a board certified urologist at New York Presbyterian Hospital/Weill Medical College of Cornell University. Each week, he’ll answer reader questions in an effort to get guys to ‘man up about health.’