The prostate gland is only present in men. It produces fluid which is added to the semen at the time of ejaculation. The normal prostate in young men is about the size of a small plum. Urine passes from the bladder to the end of the penis through a tube called the urethra. The urethra passes through-out the centre of the prostate, and is surrounded by it.
Behind the prostate is the rectum, or back passage. This is why the prostate gland can be examined by rectal examination. From the age of 40, some enlargement of the prostate occurs in all men. Only in about 1 in 10 will the enlargement cause significant symptoms or require any treatment.