The prostate gland both produces a fluid component of semen and serves as a muscle-driven switch in men between urination and ejaculation. Like our ears and nose, the prostate continues to grow with age. The normal prostate growth rate is 2.2% per year, doubling in volume every 32.6 years. Unfortunately, the prostate’s location just below the neck of the bladder, around the urethra and ejaculatory ducts, and near the rectum, affords little space for expansion. Read more.