Benign prostatic hypertrophy, also known as BPH is a slow enlargement of the prostate gland, with hypertrophy and hyperplasia of the normal tissue. The enlargement causes narrowing of the urethra and results in partial or complete obstruction. The cause is unknown, and the disorder usually occurs in men older than 50 years.
Because the condition occurs in older men, changes in hormone balances have been associated with the cause. Androgens (testosterone) and estrogen appear to contribute to the hyperplastic changes that occur. Other theories, such as those involving diet, heredity, race, and history of chronic inflammation, have been associated with BPH, but no definitive links have been made with these potential contributing factors.