Last updated: 02/17/2009

The cause of BPH is not entirely known; however, the incidence increases with advancing age. Before 40 years of age, approximately 10% of males have BPH. A small amount of hyperplasia is present in 80% of males over 40 years old. Approximately 8–31%...

of males experience moderate to severe lower urinary tract symptoms (LUTS) in their fifties. By age 80, about 80% of men have LUTS. A risk factor is the presence of normally functioning testicles; research indicates that castration can minimize prostatic enlargement. It appears that the glandular tissues that multiply abnormally use male hormones produced in the testicles differently than the normal tissues do.

Approximately 5.5 million American males have BPH. It is more prevalent in the United States and Europe, and less common among Asians. BPH is more common in men who are married rather than single, and there is a strong genetic correlation. A man's chance for developing BPH is greater if three of more family members have the condition.