• Also Known As:
  • BPH
  • Benign Prostatic Hypertrophy
  • Enlarged prostate
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What is benign prostatic hyperplasia?

Benign prostatic hyperplasia (BPH), also known as benign prostatic hypertrophy, is a progressive, non-cancerous enlargement of the prostate. The prostate is a small gland, normally about the size of a walnut, that encircles the urethra in males and produces a fluid that nourishes sperm. This fluid, along with fluid from the seminal vesicles, makes up semen.

With BPH, the volume of the prostate increases, putting pressure on the urethra, causing a slowdown in the urine stream, a hesitancy in urinating, a weak, interrupted urine stream, and/or sometimes dribbling of urine at the end of the flow. When urine cannot flow freely through the urethra, the muscular wall of the bladder thickens and becomes more sensitive to the presence of urine. This results in more frequent urination. Over time, the bladder muscle grows weak and can no longer contract with enough force to completely empty the bladder.

When urine remains in the bladder, the risk of developing a urinary tract infection (UTI) or bladder stones increases. In severe cases of BPH, urine may back up into and damage the kidneys. Rarely, BPH may prevent a man from urinating at all, a situation that requires immediate medical attention. BPH and some of its treatments can also affect sexual functioning, leading to erectile dysfunction and painful ejaculation.

The exact cause of BPH has not been identified. However, research suggests that changes in the balance of sex hormones that occur as men grow older may play a role. For some men, there may be a genetic predisposition for BPH. Approximately 50% of men under the age of 60 who have had surgical intervention, have been shown to fall within this category.


About Benign Prostatic Hyperplasia

Risk factors

Risk factors for BPH include the following:

  • Age 40 or older
  • Family history of BPH (father or brother)
  • Ethnic background – BPH is less common in Asian men than in white men and African American men; African American men are more likely to develop BPH at a younger age than white men
  • History of chronic health problems, such as obesity, type 2 diabetes, and heart disease
  • Lack of physical exercise
  • Erectile dysfunction

Signs and Symptoms

The type and severity of signs and symptoms experienced will vary from man to man and may vary over time. For many men, BPH never progresses beyond a minor to moderate annoyance; for others, it may represent a significant challenge to their quality of life.

The American Urological Association (AUA) has developed a questionnaire to help men assess the severity of their urinary symptoms and monitor the effectiveness of treatment. This questionnaire has been adopted worldwide and is known as the International Prostate Symptom Score (IPSS).

Questions on IPSS address the following:

  • Incomplete bladder emptying
  • Frequency of urination
  • Stopping and starting of urine stream
  • Urinary urgency
  • Weak urine stream
  • Straining to urinate
  • Wakening during the night to urinate (nocturia)
  • Affected man’s perceived quality of life

BPH becomes a very common condition in men as they age. Approximately 20% of men between the ages of 41 and 50 may experience BPH. According to the National Association for Continence, about 50% of men will have some degree of BPH by the time they are 60 years old, and up to 90% will be affected by age 85. While BPH does not cause prostate cancer, both may be found together.


Evaluation for BPH involves a discussion of the man’s medical and family history, a physical examination, a digital rectal examination (DRE), and an analysis of his symptoms. Laboratory, imaging, and other types of tests may be used to determine the size of the prostate and to rule out other diseases or conditions that may be causing the symptoms or making them worse.

Laboratory tests

Laboratory tests may include:

Non-laboratory tests

Non-laboratory tests may include:

  • Digital rectal exam (DRE)–to determine the approximate size of the prostate
  • Transrectal ultrasound – to help measure the size of the prostate and evaluate the volume of urine retained in the bladder
  • Cystoscopy – an evaluation of the urethra and/or bladder using a thin, flexible scope
  • Urine flow and/or pressure studies – to evaluate how fast urine can travel through the urethra and how much pressure is being put on the bladder by urine retention
  • Postvoid residual urine (PVR) studies – to measure urine left in the bladder after urinating
  • Prostate biopsy – collection of one or more small samples of prostate tissue and evaluation of its cellular structure under the microscope for abnormal cells and any signs of prostate cancer. PSA levels may be increased up to ten-fold for 8-10 weeks post biopsy.

Studies have shown that measuring the serum PSA, performing a digital rectal examination, and a transrectal ultrasound (TRUC) provide a high level of confidence in diagnosing BPH.


In many cases, treatment for BPH is not necessary and the condition may not progress in severity. For some men, symptoms may resolve completely. However, because BPH can be progressive, men with this condition should be followed to watch for complications, such as infections and bladder stones. It is recommended that a man consult his doctor if he has bothersome symptoms and immediately if he has blood in his urine, pain during urinating, or cannot urinate.

Treatment options for BPH should be discussed with a urologist. For men with mild to moderate symptoms, watchful waiting with lifestyle changes may be appropriate. For more severe cases, medications, minimally invasive procedures, and/or surgery may be the course of treatment.

View Sources

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Deters LA. (6 Nov 2016 updated.) Benign Prostatic Hypertrophy. Available online at http://emedicine.medscape.com/article/437359-overview?pa=pjcpJFziVtidyc3mPZw0nI0kS%2BN6TaVIM%2FiDWCbEIpwI33GP4LRnoLbt2MSIkCyikMxRGSC7BjbG0fgXxUgsJXf7Bj2Gvk6BKC47oRZ1BB8%3D#a7. Accessed July 27, 2017.

Barry MJ, Fowler FJ, O’Leary MP, et al. The American Urological Association Symptom Index for Benign Prostatic Hyperplasia. The Journal of Urology. 2017; 197: S189-S197. DOI: http://dx.doi.org/10.1016/j.juro.2016.10.071 American Urological Association. Management of Benign Prostatic Hyperplasia. Available online at https://www.auanet.org/guidelines/benign-prostatic-hyperplasia-(2010-reviewed-and-validity-confirmed-2014). Accessed July 27, 2017.

Mayo Clinic. (13 Nov. 2014 updated.) Benign Prostatic Hyperplasia (BPH). Available online at http://www.mayoclinic.org/diseases-conditions/benign-prostatic-hyperplasia/basics/definition/con-20030812. Accessed July 27, 2017.

Urology Care Foundation. Benign Prostatic Hyperplasia (BPH). Available online at http://www.urologyhealth.org/urologic-conditions/benign-prostatic-hyperplasia-(bph). Accessed July 27, 2017.

Cooperberg MR, Presti JC, Jr, Shinohara K, Carroll PR. Chapter 23. Neoplasms of the Prostate Gland. In: McAninch JW, Lue TF. eds. Smith and Tanagho’s General Urology, 18e New York, NY: McGraw-Hill; 2013.

Scher HI, Eastham JA. Benign and Malignant Diseases of the Prostate. In: Kasper D, Fauci A, Hauser S, Longo D, Jameson J, Loscalzo J. eds. Harrison’s Principles of Internal Medicine, 19e New York, NY: McGraw-Hill; 2014.

Miteshkumar RT , Bhooraram AC. Digital rectal examination, transrectal ultrasound, and prostate specific antigen as triple assessment diagnostic tool for benign enlargement of prostate. Natl J Med Research 2015; 5(3):244-248.

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