[Question #5468] Bruise

24 months ago
I recently had oral sex with my partner who I have been with in a committed relationship and woke up with a rather large bruise on the shaft of my penis. It is very strange as I did not have any pain we did not have any real rough sex but when I went to have a shower in the morning I noticed the bruise.  There are no cuts or bumps or anything like that, just a deep purple bruise smaller than the size of a dime.  Just curious as to know if I should be concerned with an STD and if so what STD's could cause bruising on the penis shaft?  Does/can Herpes cause bruising?  I heard that bruising could be the sign of an STD? Is this true? Looking for answers. 
Edward W. Hook M.D.
Edward W. Hook M.D.
24 months ago
Welcome to the Forum. I'll do my best to help.  A bruise occurs when blood leave blood vessels (arteries and veins) and lingers under the skin.  As the blood deteriorates, decolorization occurs, most often purple in color.  The penis is a very highly vascular part of the anatomy and while it is not common, my suspicion is that during your recent sexual encounter with your regular partner a minor blood vessel leaked some blood leaving you with the bruise you noted (after all, with an erection the penis is engorged with blood under pressure).  This is unlikely to be a pathological process and in the absence of other problems is not something I would worry about. It will likely go away on its own over time.  Certainly there are no STIs which would cause bleeding of the sort you describe.

I hope that this information is helpful.  EWH
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