I have no problem with erection, but no semen comes out from either masturbation or even intercourse. A doctor has checked for prostate problems and it is negative. I used to be able to produce semen. I am diabetic.

--Paul

You probably have a common condition called retrograde ejaculation, which is frequently seen in people with diabetes. The semen enters the penis via the ejaculatory ducts, which pass through the prostate. At the time of ejaculation, a muscle at the opening to the bladder squeezes shut. With each muscle contraction, the semen is propelled down the urethra and out the opening of the penis. However, if there is nerve damage due to diabetes, the muscle at the opening to the bladder will not close off properly, and the semen enters the bladder instead of shooting out the end of the penis.

Your urologist can diagnose this condition easily by checking your urine for semen after ejaculation. If this is the problem, you may try medication to strengthen the function of the muscle that closes the bladder. Or you may have sperm collected from the bladder to use for insemination or for in vitro fertilization.