What causes benign prostatic hyperplasia?

The cause of BPH consists of two parts: first, the age of the patient; second, the existence of functional androgen-secreting testes. Androgen in the body under the action of 5 alpha reductase, into a more active dihydrotestosterone. It acts on prostate tissue, causing obvious hyperplasia of prostate cells and muscle fiber tissue, resulting in obvious increase in prostate volume and obvious increase in lower urinary tract resistance, thus showing a series of clinical symptoms of lower urinary tract obstruction.