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The Causes and Symptoms of BPH (Enlarged Prostate)

illustration of an enlarged prostate within the male reproductive systemThe prostate is made up of thousands of tiny glands. After age 40 these glands begin to multiply and increase in size, a process called benign prostatic hyperplasia, or BPH. Almost all men develop some degree of BPH and the amount of enlargement increases with age.

Altogether, about 30% of men in the United States have enough problems from BPH to require some treatment in their lifetimes. The male hormone testosterone must be present for BPH to occur, but we still do not know exactly what causes the prostate to enlarge or why it is worse in some men than in others.

BPH (enlarged prostate) is a common part of aging for men

a concerned mature manIt is common for the prostate glad to become enlarged as man ages. As a man matures, the prostate goes through two main periods of growth. The first occurs early in puberty when the prostate doubles in size. At around age 40, the gland begins to grow again. This second growth phase often results years later in BPH.

Though the prostate continues to grow during most of a man’s life, the enlargement doesn’t usually cause problems until later in life.

BPH rarely causes symptoms before the age of 40, but more than
half of men in their sixties and as many as 90 percent in their seventies
and eighties have some symptoms of BPH

As the prostate enlarges, the layer of tissue surrounding it stops it from expanding causing the gland to press against the urethra like a clamp on a garden hose. The bladder wall becomes thicker and irritable. The bladder begins to contract even when it contains small amounts of urine, causing more frequent urination.
Eventually the bladder weakens and loses the ability to empty itself, so some of the urine remains in the bladder. The narrowing of the urethra and partial emptying of the bladder cause many of the problems associated with BPH.

Why does an enlarged prostate (BPH) occur?

Humans and dogs are the only animals who are bothered by BPH. Why just us two—we don’t know.
We know that you have to have testosterone to develop BPH. Eunuchs, castrated before puberty, never developed BPH. Conversely, getting rid of testosterone causes the prostate to shrink. But the exact level of testosterone does not correlate with the degree of BPH. And at least 10% of men with normal testosterone never get BPH. So it appears that testosterone is required for BPH to occur but does not directly cause it. Since we do not understand the causes of BPH very well, we cannot give good advice on how to prevent it. We can give good advice on how to manage and treat it.

The symptoms of an enlarged prostate (BPH)

illustration comparing normal and enlarged prostatesWhen the prostate gland enlarges, it may begin to obstruct the flow of urine through the urethra. It may also push up against the bladder causing some irritation. The most typical symptoms of BPH include:

  • A slow urinary stream
  • An interrupted stream—one that starts and stops
  • Having to strain to urinate
  • Hesitancy-having to wait before the stream will start
  • Feeling that the bladder doesn’t empty all the way
  • Urgency—having to urinate more often then when you were younger
  • Having to get up at night to urinate

These symptoms will almost always be worse at night time. In the early stages for instance, men will have hesitancy and a slow, interrupted stream at night, but after being up for a few minutes in the morning, they will urinate perfectly fine the rest of the day.
BPH can cause urinary infections or stones in the bladder. In serious cases the obstruction may lead to the inability to urinate at all, called urinary retention, which creates enough back-pressure to obstruct the ureters which drain urine from the kidneys to the bladder.

There are some imitators of BPH

Although these symptoms are most commonly due to BPH, several other problems can cause identical symptoms, even though they are not BPH. They are:

  1. Prostatitis, which is an infection in the prostate gland, and will cause the prostate to swell. Treatment with antibiotics will reduce the swelling.
  2. Urethral stricture, which is scar tissue in the urethra. It can usually be opened up with a fairly simple office or outpatient procedure.
  3. Prostate cancer may also obstruct the flow of urine just like BPH.


Prostate Cancer can cause the same symptoms as BPH

Prostate cancer is the most commonly diagnosed cancer in American men and the second leading cause of cancer death in American men. Both BPH and prostate cancer can cause the same symptoms and both are common in the same age group. Both often coexist in the same man.