Benign prostatic hyperplasia (BPH) is a non-cancerous swelling of the prostate gland. It is a common urological disorder in men over 50 years old. This swelling of the prostate causes the urethra, the tube that passes the urine out of the penis, to be squeezed and narrowed. This blocks the flow of urine out of the bladder and more pressure is needed to pass urine.
The bladder starts to contract (tense) even when it is not completely full, and eventually loses its ability to empty itself. The symptoms of BPH are linked with the narrowing of the urethra and the incomplete emptying of the bladder.