Aging changes in the male reproductive system occur primarily in the testes. Testicular tissue mass decreases and the level of the male sex hormone testosterone stay the same or decreases very slightly. There may be problems with erectile function. However, this is a general slowing, rather than a complete lack of function.
Men experience an age-related decrease in testicular size and in sperm production. In some men, there is an almost linear decline in testosterone production that becomes noticeable after the age of 40. However, many males experience no decline in testosterone levels. Both the decrease in testosterone and the decrease in sperm production cause an age-related decrease in fertility. The loss of testosterone also results in a decrease in bone and muscle mass in the aging male. The loss of testosterone may also contribute to sexual dysfunction with age in men.
Fertility: The tubes that carry sperm may become less elastic (a process called sclerosis). The testes continue to produce sperm, but the rate of sperm cell production slows. The epididymis, seminal vesicles, and prostate gland lose some of their surface cells but continue to produce the fluid that helps carry sperm.
Urinary function: The prostate gland enlarges with age as some of the prostate tissue is replaced with a scarlike tissue. This condition, called benign prostatic hypertrophy (BPH), affects about 50% of men. This may cause problems with slowed urination, as well as with ejaculation.
Effect of changes: Fertility varies from man to man, and age is not a good predictor of male fertility. Prostate function is not closely related to fertility, and a man can father children even if his prostate gland has been removed. The volume of fluid ejaculated usually remains the same, but there are fewer living sperm in the fluid.
Decreases in the sex drive (libido) may occur in some men. Sexual responses may become slower and less intense. This may be related to decreased testosterone level, but it may also result from psychological or social changes related to aging, illness, chronic conditions, or medications.
Common problems: Erectile dysfunction (ED) may be a concern for aging men. It is normal for erections to occur less frequently than when a man was younger, and aging men often have less ability to experience repeated ejaculation. However, ED is most often the result of a medical or psychological problem rather than simple aging, and 90% of ED is believed to be of medical rather than psychological origin. Medications (especially those used to treat hypertension and certain other conditions) can cause some men to be unable to develop or maintain enough of an erection for intercourse. Disorders such as diabetes can also cause ED.
BPH may eventually interfere with urination. The enlarged prostate partially blocks the tube that drains the urinary bladder (urethra). Changes in the prostate gland make elderly men more likely to have urinary tract infections.
Backup of urine into the kidneys (vesicoureteral reflux) may develop if the bladder is not fully drained. If this is not treated, it can eventually lead to kidney failure.
Prostate gland infections or inflammation ( prostatitis) may also occur.
Prostate cancer becomes more common as men age. It is one of the most frequent causes of cancer death in men. Bladder cancer also becomes more common with age. Testicular cancers are possible, but these occur more often in younger men.
Prevention: Many physical age-related changes, such as prostate enlargement or testicular atrophy, are not preventable. Getting treatment for health disorders (such as high blood pressure and diabetes) that lead to changes in urinary and sexual health may prevent later problems with urinary and sexual function.
Changes in sexual response are most often related to factors other than simple aging. Older men are more likely to have good sex if they have continued to have sexual activity during middle age. Sometimes, however, decrease in sex drive is related to an underlying condition such as depression, stress or a medication side effect.