SummaryBenign prostatic hyperplasia (BPH) is a common benign tumor that develops in men and is bothersome in elderly patients. The prevalence of lower urinary tract symptoms in the general population increases with aging. The normal prostate weighs 20 ± 6 g in men aged 21–30 years. The prevalence of pathological BPH is only 8% at the 4th decade of life; however, 50% of the male population develop pathological BPH at age 51–60 years. The average weight of a prostate that is recognized at autopsy as having BPH is 33 ± 16 g. Men aged 70–79 years are 4.6 times more likely (95% confidence interval, 2.1–10.1) than those aged 40–49 years to have sought health care because of urinary symptoms. Health care-seeking behavior is influenced by BPH-relat...