A weak urine stream, frequent trips to the bathroom, and waking up several times a night to urinate can make it harder to sleep and get through the day.
If you’re wondering what causes enlarged prostate, the most common reason is benign prostatic hyperplasia (BPH), an age-related condition that isn’t cancer.
Hormonal changes over time are the main reason the prostate continues to grow. Family history, weight, diabetes, and lower activity levels may also increase the likelihood of developing BPH.
Where Is the Prostate?
The prostate sits just below the bladder and surrounds the urethra, the tube that carries urine out of the body. As the prostate grows, it presses on the urethra and narrows the space urine flows through.
Even a small increase in size can make it harder to urinate. Over time, the bladder has to work harder to push urine past the blockage.
Why Does Enlarged Prostate Happen?
The prostate usually grows because of hormone changes that happen with age. These changes create conditions that allow prostate cells to keep multiplying.
Other factors that may increase the likelihood of BPH include:
- Getting older
- A family history of prostate enlargement
- Being overweight
- Insulin resistance
- Type 2 diabetes
- Lower levels of physical activity
In most men, BPH develops because of a combination of aging, hormone changes, and metabolic health.
How Does an Enlarged Prostate Cause Urinary Symptoms?
As the prostate enlarges, it narrows the urethra. This slows the flow of urine and forces the bladder to work harder.
You may notice:
- A weak or slow urine stream
- Trouble starting urination
- Stop-and-start flow
- A feeling that your bladder isn’t empty
- Frequent urination, especially at night
- Sudden urges to urinate
Could My Symptoms Be Caused by Something Else?
BPH is a common cause of urinary symptoms, but it isn’t the only one. Similar symptoms can also occur with:
- Urinary tract infections
- Prostatitis (inflammation of the prostate)
- Overactive bladder
- Prostate cancer
- Bladder cancer
What Causes Enlarged Prostate? See a Urologist in Eugene–Springfield, OR
If you’re still asking what causes enlarged prostate, the most common cause is benign prostatic hyperplasia (BPH). This noncancerous condition develops slowly as hormone levels change with age. Family history, weight, and diabetes may also play a role.
Other conditions can cause similar urinary symptoms. An evaluation can help determine what’s causing your symptoms.
If you’re dealing with frequent urination, a weak stream, or trouble emptying your bladder in the Eugene–Springfield, OR area, schedule an appointment with a urologist to discuss your treatment options.

