Okay, try not to freak out. This is called hematospermia or hemospermia and it's usually not cancer, says Fisch. This could be a one-time thing or a persistent problem, and while it usually goes away on its own, you probably want to check with a doctor if it continues.

"Blood in the semen almost always has a benign cause," Dr. Abraham Morgentaler, director of Men's Health Boston and associate clinical professor of urology at Harvard Medical School, tells BuzzFeed Life. It could be from inflammation or infection in the prostate or seminal vesicles, stones in the ejaculatory ducts, or a whole list of other things. Sometimes doctors can't figure out the precise cause, but it's often nothing major, says Morgentaler. That said, if you're seeing blood in your urine, definitely get that checked out since it might be something more serious.