Burning when you pee, needing to go again and again, or cloudy urine can all be signs of a urinary tract infection, or UTI.2,3 UTIs are common, especially in women, and most are easy to treat with antibiotics.4 This page explains what a UTI is, which signs medical sources say need prompt care, how UTIs are diagnosed and treated, why some women keep getting them, and what the evidence says about prevention.

What a UTI is

UTIs are common infections that happen when bacteria, often from the skin or rectum, enter the urethra and infect the urinary tract.2

  • Bladder infection. A bladder infection, also called cystitis, is the most common type of UTI.1,2 People often use “UTI” to mean a bladder infection.1
  • Kidney infection. A kidney infection, also called pyelonephritis, is less common than a bladder infection but is more serious.2 If a bladder infection isn’t treated, it can spread to one or both kidneys.1

About half of all women will develop a bladder infection in their lifetime, according to NIDDK.1 When they’re diagnosed early and treated properly, the National Institute of Diabetes and Digestive and Kidney Diseases (NIDDK) says most bladder infections don’t lead to complications.1

Common symptoms

Symptoms of a bladder infection can include:2,3

  • Pain or burning when you urinate
  • Needing to urinate often, or feeling a strong urge even when little urine comes out
  • Pressure, cramping, or discomfort in the lower belly or groin
  • Cloudy, bloody, or strong-smelling urine

MedlinePlus adds that some people have a low-grade fever.5 In older people, mental changes or confusion are often the only signs of a UTI.5

Signs that need prompt care

The Centers for Disease Control and Prevention (CDC) says to see a health care professional if you have one or more symptoms of a UTI, or any symptom that is severe or concerning.2 Sources name some situations where care shouldn’t wait:

  • Signs of a kidney infection. NIDDK says quick treatment is important if you have symptoms of a kidney infection, such as fever and chills, nausea or vomiting, or pain in your back, side, or groin.3 MedlinePlus says to contact your provider right away if you have back or side pain, chills, fever, or vomiting.5 Kidney infections may cause severe pain and serious health problems if they’re not treated early.3
  • Blood in your urine. The U.S. Office on Women’s Health (OWH) says that if you see blood in your urine, tell a doctor or nurse right away.4
  • UTI symptoms during pregnancy. OWH says that if you’re pregnant and have symptoms of a UTI, see your doctor or nurse right away.4 More on why is in UTIs during pregnancy.
  • Symptoms that don’t get better or come back. CDC says to talk with a health care professional if your symptoms don’t improve after starting antibiotics or if they get worse.2 MedlinePlus also says to contact your provider if UTI symptoms come back shortly after you’ve been treated.5

Rarely, the infection can get into the bloodstream, which OWH describes as life-threatening.4

Why women get UTIs more often

Women have a short urethra that sits close to the anus, a source of bacteria, so bacteria may more easily enter the urinary tract.1 OWH notes that the opening of the urethra is also close to the vagina.4

Sources list other things that make UTIs more likely, including:1,2,4

  • Being sexually active
  • Using a diaphragm or spermicide for birth control
  • Pregnancy
  • Having gone through menopause
  • Having had a UTI before
  • Trouble emptying the bladder completely
  • Using, or having recently used, a urinary catheter
  • Something that blocks the flow of urine, such as a kidney stone
  • Diabetes or problems with the immune system

Sexual activity can move germs toward the urethra.4 But CDC notes that a UTI is not a sexually transmitted infection.2

How a UTI is diagnosed

A health care professional may diagnose a UTI by asking about your symptoms, doing a physical exam, and ordering urine tests if needed.2 For a urine test, OWH says you’ll usually clean your genital area with a special wipe and then collect urine midstream in a cup.4

  • Urinalysis checks the urine for blood and white blood cells, which the body makes when it’s fighting a bacterial infection.6
  • Urine culture identifies the bacteria in the urine and may help choose the best antibiotic; results typically take a few days.5,6
  • Blood tests may be used to look for a more serious infection, such as a kidney infection.6

If you have repeat infections, NIDDK says a health care professional may also use imaging of the urinary tract, or cystoscopy to look inside the urethra and bladder, to help find the cause.6 A 2025 guideline from the American Urological Association (AUA) and two partner societies says these tests should not routinely be done when a woman is first evaluated for recurrent UTIs.7

Treatment and antibiotics

This section describes what medical sources say. It isn’t personal advice; your clinician can help you work out what fits your situation.

If a bladder infection is caused by bacteria, a health care professional will likely prescribe antibiotics.8 MedlinePlus says bladder infection symptoms most often go away within 24 to 48 hours after treatment begins, while symptoms of a kidney infection may take a week or longer to go away.5 People who are very sick from a kidney infection may need antibiotics through an IV.8

Taking antibiotics as prescribed. NIDDK says to finish your entire treatment as prescribed, even if your symptoms go away, and warns that not following instructions could let the bacteria develop antibiotic resistance, making the infection harder to treat.8 CDC also advises not sharing antibiotics with others, not saving them for later, and asking a health care professional how to safely discard leftovers.2

Side effects. Like all medicines, antibiotics can cause side effects, from mild rashes to serious problems such as severe allergic reactions, drug-resistant infections, and C. diff infection, which causes diarrhea.2 CDC says to contact a health care professional if you have side effects while taking an antibiotic.2

Not every positive urine test needs antibiotics. Sometimes bacteria are found in the urine without causing symptoms; this is called asymptomatic bacteriuria.2 CDC says most people with it don’t need treatment, but some people, such as pregnant women, may.2

Recurrent UTIs

Some women get UTIs again and again.5 About a quarter of women who get a bladder infection will have repeat infections, according to NIDDK.1

Organizations define recurrent UTIs a little differently:

  • OWH says women who get two UTIs in six months or three in a year have recurrent UTIs.4
  • The AUA guideline notes that there are multiple definitions and uses the most common one: two episodes of bladder infection within a six-month period sometime within the past year, with symptoms clearing between episodes.7

For women with recurrent UTIs, the AUA guideline says clinicians should do a urinalysis and urine culture with each episode before starting treatment.7 It also recommends treating each episode with as short a course of antibiotics as reasonable, generally no longer than seven days.7 The guideline was written in part to prevent inappropriate antibiotic use and reduce the risk of antibiotic resistance.9

Options sources describe for women with recurrent UTIs include:

  • Antibiotics to prevent infections. MedlinePlus says a provider may suggest a single dose of an antibiotic after sex, a single daily dose, or a short course kept at home to start if symptoms begin.5 The AUA says clinicians may prescribe preventive antibiotics after discussing the risks, benefits, and alternatives.7 For women whose UTIs are linked to sex, the guideline says antibiotics taken before or after sex have been shown to be effective and safe.7
  • Non-antibiotic options. The AUA recommends that clinicians offer cranberry as an option, says they may offer a medicine called methenamine hippurate, and says they should tell patients that D-mannose alone may not be effective.7 More on cranberry is below.
  • Vaginal estrogen for women in perimenopause or after menopause (see UTIs after menopause).

If symptoms continue after an infection has been cleared, the AUA says clinicians should look for other causes.7

Prevention: what the evidence says

OWH says you can take steps to help prevent a UTI but may still get one.4 Sources don’t all agree on which everyday habits make a difference, so this section says who recommends what.

Fluids

NIDDK says drinking enough liquids can help prevent or relieve bladder infections, and that water is best.10 OWH suggests trying to drink six to eight glasses of fluid a day.4 For women with recurrent UTIs who drink less than 1.5 liters (about 50 ounces) of water a day, the AUA guideline says clinicians may offer increased water intake as prevention, a conditional recommendation based on lower-grade evidence.7

Bathroom and hygiene habits

CDC, NIDDK, and OWH list habits such as urinating after sex, wiping front to back, not holding urine when you feel the urge, taking showers instead of baths, avoiding douching and genital sprays, and wearing cotton underwear and loose clothes that don’t trap moisture.2,4,8

The AUA guideline, which focuses on women with recurrent UTIs, sees it differently. It calls these “commonly held myths” and says case-control studies show that front-to-back wiping, urinating before and after sex, avoiding hot tubs, tampon use, and douching do not play a role in preventing recurrent UTIs.7 If you keep getting UTIs despite these habits, you can ask your clinician about the options described in Recurrent UTIs.

Birth control

NIDDK says diaphragms, unlubricated condoms, and spermicide may increase your chances of getting a bladder infection, and suggests talking with your health care professional about switching methods if you have repeat infections.8 The AUA guideline agrees that women using barrier methods or spermicide may consider changing, and says spermicide likely raises risk by harming helpful bacteria in the vagina.7

Cranberry

Cranberry products do not treat a UTI you already have.10,11 The National Center for Complementary and Integrative Health (NCCIH) says people who think they have a UTI should see a health care provider and should not use cranberry instead of a proven treatment.11

For prevention, the evidence is mixed, and sources describe it with different levels of confidence:

  • NIDDK says some research suggests cranberry may help prevent bladder infections, but there isn’t enough evidence to be sure.10 NCCIH says its effectiveness is still in question because of inconsistent findings.11
  • A 2023 Cochrane review of 50 trials found that the evidence supports cranberry products to reduce the risk of UTIs in women with recurrent UTIs, but not in older people in care settings, people with bladder-emptying problems, or pregnant women.12
  • The AUA guideline recommends that clinicians offer cranberry as an option for women with recurrent UTIs.7
  • Since 2020, the Food and Drug Administration has let manufacturers say on labels that there is “limited” evidence that cranberry supplements may reduce the risk of recurrent UTIs in healthy women, and “limited and inconsistent” evidence for cranberry juice drinks.11

NCCIH says there is conflicting evidence on whether cranberry interacts with the blood thinner warfarin, and suggests talking with your health care provider before using cranberry products if you take warfarin or any other medicine.11

UTIs during pregnancy

Pregnancy hormones can change the bacteria in the urinary tract, and the growing uterus can make it hard to empty the bladder completely, both of which make UTIs more likely.4 Bladder infections during pregnancy are more likely to spread to the kidneys.1 OWH says that untreated UTIs could lead to kidney infections and to problems during pregnancy, including premature birth, low birth weight, and high blood pressure that can lead to preeclampsia.4

That’s why urine is checked even without symptoms. The U.S. Preventive Services Task Force (USPSTF) recommends screening pregnant people for asymptomatic bacteriuria with a urine culture, a “B” grade recommendation from 2019.13 It advises doing the culture at the first prenatal visit or at 12 to 16 weeks of pregnancy, whichever is earlier.13 The USPSTF found that treating bacteria found this way can reduce kidney infections in pregnancy.13

If you’re pregnant and have UTI symptoms, OWH says to see your doctor or nurse right away, and that your doctor will give you an antibiotic that is safe to take during pregnancy.4 MedlinePlus says to tell your provider if you might be pregnant before taking UTI medicines.5 Fever during pregnancy has its own guidance; see Fever and infection in our guide to urgent warning signs.

UTIs after menopause

Menopause raises the risk of UTIs.5 OWH explains that after menopause, loss of estrogen makes vaginal tissue thin and dry, which can make it easier for harmful bacteria to grow.4

The AUA guideline says that in women in perimenopause or after menopause who have recurrent UTIs, clinicians should recommend vaginal estrogen to reduce the risk of future UTIs if there’s no reason they can’t use it.7 It distinguishes this from estrogen taken by mouth or other whole-body forms, which have not been shown to reduce UTIs.7 The guideline says systemic risks from vaginal estrogen are minimal because little is absorbed, and that for women with a history of breast cancer it should be considered together with their oncologist.7

Read more: Perimenopause and menopause covers other vaginal and urinary changes, and menopause hormone therapy covers estrogen’s broader benefits and risks.

When it might be something else

Not every burning or urgent feeling is a UTI. CDC notes that UTI symptoms can be similar to symptoms of a sexually transmitted infection (STI), and suggests asking a health care professional whether you should be tested.2 Our guide to STI testing explains who should be tested and when.

The AUA guideline says a range of conditions can cause symptoms that overlap with a bladder infection, including bacterial or fungal vaginal infections, skin inflammation of the vulva (vulvar dermatitis), genitourinary syndrome of menopause, urinary stones, overactive bladder, bladder pain syndrome (interstitial cystitis), and pelvic floor muscle pain.7 If you also have vaginal itching, discharge, or pain with sex, our guide to painful sex and vaginal or vulvar symptoms may help.

What we don’t know yet

  • Everyday prevention habits. CDC, NIDDK, and OWH recommend habits such as urinating after sex and wiping front to back, while the AUA guideline on recurrent UTIs says studies show these don’t play a role in preventing recurrent UTIs.2,4,7,8
  • Cranberry. NCCIH notes that processing cranberries into tablets or capsules can lower the amount of the compounds thought to work.11 The Cochrane review found it unclear whether juice and tablets differ, because the certainty of that evidence was very low.12
  • Screening timing in pregnancy. The USPSTF says there is little evidence on the best timing and frequency of screening for bacteria in the urine during pregnancy.13 Its recommendation dates from September 24, 2019, and could be updated.13

Questions to ask your doctor

  • Do my symptoms sound like a bladder infection, a kidney infection, or something else?
  • Will you test my urine, and will you send a culture?
  • What side effects should I watch for with this antibiotic?
  • Could this be an STI or a vaginal infection instead? Should I be tested?
  • I keep getting UTIs. Do I meet the definition of recurrent UTIs, and what prevention options fit me? Could my birth control play a role?
  • I’m in perimenopause or past menopause. Is vaginal estrogen an option for me?
  • I’m pregnant. Has my urine been checked for bacteria, and what should I do if I get symptoms?
  • Is cranberry worth trying for me, and does it interact with any of my medicines?

This article summarizes published research and official health information. It has not been reviewed by a clinician and is not medical advice. How we source.

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