The prostate is a gland， weighing 25 gram， below the bladder. Because it is situated around the urethra (bladder pipe)， enlargement causes obstruction in urethra. Enlargement occurs naturally with age， and might be accompanied by cancerous change.
Symptoms are usually slow in onset， starting with dribbling， getting up at night， weak stream， urgency and hesitancy. The symptoms tend to get worse progressively， and might culminate in retention.
After the age of 45， men should have their prostates checked annually， including blood tests and a rectal examination.