A typical urinary tract infection does not usually cause a false-positive pregnancy test.

Pregnancy tests detect human chorionic gonadotropin, or hCG. The bacteria that cause most UTIs do not produce this hormone. However, rare interference has been reported with some urine pregnancy tests in people with upper urinary tract infections.

Because you can be pregnant and have a UTI at the same time, do not assume a positive result is wrong. Repeat the test correctly and contact a healthcare professional if the result is unexpected or unclear.

Quick Answer

No, a typical UTI does not cause a false-positive pregnancy test. Pregnancy tests detect hCG, a hormone that bacteria don’t produce. However, a small 2025 study found rare false positives in patients with upper urinary tract (kidney) infections, likely due to a urinary protein called uromodulin. If you have UTI symptoms and a positive pregnancy test, don’t assume the result is wrong — retest correctly and contact a healthcare professional, since you can be pregnant and have a UTI at the same time. – Clinton Women’s Healthcare Team

How Pregnancy Tests Work

Pregnancy tests detect hCG, a hormone that begins to rise after implantation.

There are two main types:

  • Urine tests, including home pregnancy tests
  • Blood tests, which can confirm pregnancy and measure the amount of hCG

Home tests are generally reliable when used correctly. Testing too early is more likely to cause a false negative than a false positive.

For the best result:

  • Check the expiration date.
  • Follow the instructions for that brand.
  • Read the result within the stated time.
  • Make sure the control line or symbol appears.
  • Use first-morning urine when testing early.

Can a UTI Cause a False Positive?

Most UTIs do not affect pregnancy tests

A routine bladder infection should not make a pregnancy test positive because the test detects hCG, not bacteria.

UTI symptoms such as burning, urgency, or cloudy urine do not explain away a positive pregnancy test.

Rare interference is possible

A small 2025 study reported false-positive urine hCG results in 15 patients with upper urinary tract infections. Researchers suggested that a urinary protein called uromodulin may have interfered with some tests.

This finding has important limitations:

  • The study was small.
  • It involved upper urinary tract infections.
  • It may not apply to all home pregnancy tests.
  • It does not show that ordinary UTIs commonly cause false positives.

A positive result should therefore be treated as potentially accurate until confirmed.

Can UTI Symptoms Feel Like Early Pregnancy?

Some symptoms overlap, especially frequent urination and lower abdominal discomfort.

Symptoms more commonly linked to a UTI

  • Burning or pain while urinating
  • A strong or frequent urge to urinate
  • Passing small amounts of urine
  • Cloudy or strong-smelling urine
  • Blood in the urine
  • Lower abdominal discomfort

Symptoms more commonly linked to early pregnancy

  • A missed period
  • Breast tenderness
  • Nausea
  • Fatigue
  • Mild cramping
  • Increased urination

Symptoms alone cannot confirm either condition.

Can UTI Antibiotics Cause a False Positive?

Most antibiotics do not affect pregnancy-test results.

The main medication-related exception is fertility medicine containing hCG. An hCG trigger injection may cause a positive test if you test too soon after treatment.

Tell your healthcare professional about any:

  • Prescription medicines
  • Over-the-counter medicines
  • Fertility treatments
  • Vitamins or supplements

Do not stop a prescribed antibiotic without speaking with the clinician who prescribed it.

Other Reasons for a Positive Pregnancy Test

A genuine pregnancy

The result may simply be correct. Even a faint line can indicate pregnancy if it appears within the test’s reading window.

A very early pregnancy loss

A pregnancy may produce enough hCG for a positive result and then stop developing shortly afterward. This is often called a chemical pregnancy.

In this case, the first test detected real hCG and was not necessarily false.

Recent pregnancy or pregnancy loss

hCG may remain in the body for a period after:

  • Childbirth
  • Miscarriage
  • Abortion
  • Treatment for an ectopic pregnancy

Fertility medication

Medicines containing hCG can produce a positive result before pregnancy can be confirmed.

Reading the test too late

Evaporation or indent lines may appear after the test’s reading window. Do not interpret a test several hours later.

An expired or incorrectly used test

Results may be unreliable if:

  • The test has expired or is damaged.
  • Too much or too little urine was used.
  • The instructions were not followed.
  • The control line did not appear.
  • A contaminated container was used.

Rare medical or laboratory causes

Some uncommon medical conditions or laboratory interferences can cause unexpected hCG results. A clinician may investigate these when pregnancy cannot be confirmed.

What to Do After a Positive Test With UTI Symptoms

1. Check the test

Confirm that:

  • It was not expired.
  • The control indicator appeared.
  • You read it at the correct time.
  • You followed the instructions.

2. Repeat the test

Use a new, unexpired test. First-morning urine may be helpful when testing early.

Avoid drinking excessive water beforehand because diluted urine may cause a false negative.

3. Contact a healthcare professional

A clinician may recommend:

  • Another urine pregnancy test
  • A blood hCG test
  • Repeat blood testing
  • Urinalysis
  • A urine culture
  • Ultrasound when appropriate

4. Get the UTI evaluated

Do not ignore urinary symptoms, especially if pregnancy is possible.

Tell the clinician that you may be pregnant so they can choose appropriate testing and treatment.

Do not use leftover antibiotics or medication prescribed for someone else.

Why UTIs During Pregnancy Need Treatment

A UTI can move from the bladder to the kidneys if it is not treated.

During pregnancy, UTIs may also increase the risk of complications. A healthcare professional can confirm the infection, select an appropriate antibiotic, and decide whether follow-up testing is needed.

When to Seek Urgent Medical Care

Seek prompt medical care for UTI symptoms with:

  • Fever
  • Chills
  • Back or side pain
  • Nausea or vomiting
  • Increasing weakness

These symptoms may indicate a kidney infection.

Seek urgent or emergency care for a positive pregnancy test with:

  • Severe abdominal or pelvic pain
  • Pain mainly on one side
  • Heavy vaginal bleeding
  • Shoulder pain
  • Dizziness or fainting
  • Severe weakness

These symptoms can occur with an ectopic pregnancy or another serious complication.

Call 911 or go to the nearest emergency department for severe pain, fainting, heavy bleeding, confusion, or difficulty breathing.

Frequently Asked Questions

Can bacteria in urine make a pregnancy test positive?

Usually not. Pregnancy tests detect hCG, not bacteria.

Can white blood cells affect a pregnancy test?

White blood cells are not a common cause of false-positive pregnancy tests. Limited research has linked high urinary white blood cell levels with rare interference in some upper urinary tract infections.

Can blood in urine cause a false positive?

Blood in the urine does not automatically cause a positive result. However, visibly bloody urine can make a home test harder to interpret and should be evaluated.

Can nitrites affect a pregnancy test?

Nitrites may suggest a bacterial UTI, but they are not an established cause of false-positive pregnancy tests.

Can antibiotics cause a false-positive test?

Most antibiotics do not. Fertility medicines containing hCG are a more recognized cause.

Can you be pregnant and have a UTI?

Yes. Both can occur at the same time.

What if one test is positive and another is negative?

Repeat the test using first-morning urine and follow the instructions carefully. Contact a healthcare professional if the results remain inconsistent.

The Bottom Line

A routine UTI is unlikely to cause a false-positive pregnancy test. Rare interference has been reported with some urine tests in people with upper urinary tract infections, but this is uncommon.

Do not dismiss a positive result because you have UTI symptoms. Repeat the test correctly and seek medical confirmation.

At Clinton Women’s Healthcare, our team helps patients understand unexpected pregnancy-test results, urinary symptoms, and other women’s health concerns. We provide OB-GYN, pregnancy, prenatal and gynecologic care in Utica, Clarkston, and Macomb, Michigan.

Contact Clinton Women’s Healthcare to schedule an appointment and discuss your symptoms and next steps. Seek emergency care for severe pain, fainting, heavy bleeding, fever, confusion, or difficulty breathing.