The prostate is a gland found only in men. It’s located in front of the rectum and underneath the urinary bladder, and is about the size of a walnut. Cells found in the prostate produce some of the fluid that protects and nourishes sperm cells in a man’s semen. Behind the prostate gland are the seminal vesicles that make most of the fluid for semen. The urethra is the tube that carries urine and semen out of the body and runs through the prostate.
Male hormones, called androgens, are responsible for the development of the prostate in a male fetus. Testosterone is the most common androgen. The prostate continues to grow until a man reaches adulthood. Many men experience continued growth of the prostate throughout life, which is a normal part of the aging process.