Blood in Urine: 5 Common Causes & What to Do

Updated in April 2022

Blood in urine can be diagnosed as hematuria or hemoglobinuria depending on the quantity of blood cells noted in the urine under microscopy. Nost times, bloody urine does not cause symptoms, however some people may experience burning with urination, pink urine or the appearance of strings in the urine, depending on the underlying cause. 

The presence of blood in the urine is usually related to kidney or urinary tract problems, however it can also happen following intense physical activity (which usually resolves in less than 24 hours). In women, blood in the urine can also be related to menstruation, which is not a cause for concern. 

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The main causes of blood in the urine include: 

1. Menstruation

It is common to see blood in urine during your period, especially in the first few days. As your cycle progresses, urine should return to its normal color, although a urine test may still reveal some blood cells in the urine. This is why urine testing during a period is not recommended, as it can interfere with the results. 

What to do: Blood in the urine is normal during your period, and therefore it does not require treatment. If you notice bloody urine for several days, or if it occurs on other days of your cycle, you should see your doctor for assessment to investigate the cause and initiate treatment as necessary. 

2. UTI

A UTI, or urinary tract infection, is most common in women. It can cause symptoms like urgency, pain with urination and lower abdominal pressure. Learn more about common UTI symptoms.

The presence of blood in this case is more common when an infection is in its most advanced stage. In addition to blood cells, a urine test will also reveal high quantities of bacteria, leukocytes and epithelial cells. 

What to do: It is important to follow-up with your doctor to confirm a UTI, as it requires treatment with antibiotics depending on the bacteria causing infection. Read more about UTI treatment and how it can be treated with medication and natural options.

3. Kidney stones 

The presence of kidney stones is most common in adults, but can occur at any age. It causes symptoms like burning with urination, intense lower back pain and nausea. See what can cause kidney stones and what other symptoms that can emerge.

Urine testing will reveal the presence of blood cells as well as crystals or particles depending on the type of kidney stone. 

What to do: Kidney stones are a medical emergency due to the intense pain they can cause. You should proceed to the emergency room immediately to confirm a diagnosis, especially if you are unable to pass urine. 

In some cases, medication to help with elimination of the stone can be prescribed. However, if the stone does not pass or if it is too big, a procedure may be needed to destroy or remove the stone. 

4. Medications 

Some anticoagulant medication, like warfarin or aspirin, can cause blood in the urine, especially in older adults. 

What to do: In these cases, you should inform the prescriber of the symptom, as a dose change or medication change may be necessary. 

5. Renal, bladder or prostate cancer 

Blood in the urine can be a sign of kidney, bladder or prostate cancer. It is one of the most common symptoms of these cancers in men. These cancers can also cause symptoms like urinary incontinence, pain with urination and weight loss for no apparent cause. 

What to do: You should consult your doctor if you experience these symptoms or if bloody urine emerges with no apparent cause. The quicker a diagnosis is confirmed, the faster treatment can be initiated, which can improve chance of cure. 

Blood in urine during pregnancy

Blood in the urine during pregnancy is usually caused by a UTI. However, the blood can come from the vagina and mix with the urine. Vaginal bleeding can indicate more serious problems, like placental abruption, which require immediate assessment to ensure maternal and fetal health. 

Learn more about what can cause vaginal bleeding during pregnancy.

Newborns with blood in urine 

Newborns who have blood in urine is not a serious concern, as it can be caused by the presence of crystals in the urinary tract. These crystals can give urine a red or pinkish color, which looks like blood. 

Increasing fluid intake in newborns is essential for diluting the urine to bring it to a more normal color. If the dark color does not resolve with increasing fluids, the newborn should be assessed immediately. 

When to go to the doctor

You should see your doctor if the bloody urine persists for over 48 hours, if you have difficulty urinating, or if you have other symptoms like fever over  38ºC (or 100.4ºF), intense pain with urination, or vomiting. 

To identify the cause of urine in the blood, the doctor may order testing like an ultrasound, CT scan or cystoscopy.