What Happens If You Get a UTI While Pregnant? Risks and Safe Antibiotic Treatments

A urinary tract infection (UTI) happens when bacteria invade your bladder or kidneys and cause an infection. UTIs are very common. And sometimes it’s OK to wait a few days before seeing a healthcare provider — unless you’re pregnant. 

UTIs during pregnancy can lead to serious infections and increase the risk of going into preterm labor. To avoid these risks, it’s important to start treatment as soon as possible. But spotting a UTI during pregnancy can be tricky since it might not cause any symptoms. And you might be concerned about taking medications to treat a UTI during pregnancy. But there are safe treatments for UTIs during pregnancy. 

Why are UTIs more common during pregnancy?

UTIs are more likely to develop during pregnancy due to:

• Changing hormone levels

• Shifts to your vaginal microbiome

• Physical pressure from your growing uterus, which can trap urine in your bladder and give bacteria a place to grow

You’re most likely to develop a UTI during weeks 6 to 24 of pregnancy.

What are the symptoms of a UTI during pregnancy?

Symptoms of a UTI during pregnancy may be the same as those of a regular UTI. The most common signs of a UTI during pregnancy are:

• A need to pee frequently

• An urgent need to pee even when your bladder is empty

• Pain or burning when you pee

• Discomfort if you try to hold your pee

• Stomach or pelvic pain

• Back or flank pain (kidney pain)

• Cloudy urine

• Blood-tinged urine

Some of these symptoms overlap with normal changes during pregnancy. For example, it’s common to need to go to the bathroom frequently when you’re pregnant. But pregnancy shouldn’t cause other UTI symptoms, like pain or burning when you pee or blood in your urine. If you aren’t sure about your symptoms, it’s a good idea to talk with your healthcare provider.

If you develop a fever along with UTI symptoms, that could mean the infection has moved beyond your bladder and into your kidneys. This is called pyelonephritis, and it’s a much more serious infection and can result in long-term problems for you and your growing baby. 

Any fever during pregnancy is a sign you should get medical treatment right away.

How can you test for a UTI while pregnant?

A urine sample can show whether or not you have a UTI. Your provider will use an in-office urinalysis to check your urine for signs of infection each time you give a sample at a prenatal visit. A urinalysis gives results in minutes, which means you can start treatment for a UTI right away if you need it. 

Your provider can then send your sample to a lab for a urine culture. This test will show if any bacteria is growing in your urine. Laboratory specialists can do more testing to figure out the type of bacteria. 

But, if you have symptoms of a UTI, don’t wait for your next prenatal appointment — get checked for a UTI as soon as possible. 

Which antibiotics are safe during pregnancy?

There are antibiotics for UTIs that are safe to take during pregnancy. These antibiotics tend to be older and very well studied, so there’s a lot of information showing that they’re safe. But these antibiotics need to be taken for longer than the usual course of 3 to 5 days (or fewer). 

No matter which antibiotic your provider prescribes, it’s important to finish the entire course — even if you start to feel better. If you don't finish your antibiotics, the infection could come back and be resistant (immune) to antibiotics. 

Amoxicillin 

Amoxicillin is part of the penicillin family of antibiotics. It’s a first-choice antibiotic for UTIs during pregnancy. Sometimes, healthcare providers prescribe amoxicillin / clavulanic acid (Augmentin) instead. This is a combination medication that can work better against some bacteria.

Amoxicillin and augmentin are usually taken 2 to 3 times per day for 5 to 7 days.

Cephalexin 

Cephalexin may also be a first-choice antibiotic for UTIs during pregnancy. It’s generally considered safe throughout pregnancy as well. Cephalexin is usually taken 4 times per day for 5 to 7 days. 

Cephalexin is part of the cephalosporins antibiotic family. Sometimes other cephalosporins, like cefuroxime and cefpodoxime, can be used to treat a UTI during pregnancy. 

Which antibiotics are not safe during pregnancy?

Some antibiotics that are commonly used to treat UTIs can’t be taken during pregnancy. 

Nitrofurantoin (Macrobid)

Nitrofurantoin (Macrobid) is one of the most commonly used antibiotics for bladder infections. But there’s mixed data on how safe it is to use during the first trimester. 

In general, this antibiotic should be avoided during early pregnancy — unless it’s the only option. But you can safely take nitrofurantoin during your second trimester and most of your third trimester.

However, nitrofurantoin should be avoided at the very end of a pregnancy. Studies have found that taking it during the last 30 days of pregnancy may raise the risk of infant jaundice after birth.

Sulfamethoxazole / trimethoprim (Bactrim)

Like nitrofurantoin, sulfamethoxazole / trimethoprim (Bactrim) has conflicting information on how safe it is in the first trimester. It’s typically avoided during pregnancy unless there are no other options.

Sulfamethoxazole / trimethoprim should not be taken at the very end of pregnancy either. Taking it at this time can cause a serious form of infant jaundice that can lead to brain damage.

Fluoroquinolones

Fluoroquinolone antibiotics, like ciprofloxacin and levofloxacin, are popular treatments for UTIs outside of pregnancy. But they aren't used much during pregnancy because they’re linked to an increased risk of defects. Some studies have reported that these risks are low because the medications are only taken for a few days. But it’s best to avoid them unless there are no other options. 

What else can you do to treat a UTI when you’re pregnant?

Antibiotics for a UTI take time to start working. You might be wondering if there is anything you can do to relieve your symptoms while you wait.

Here are some things that can help you stay comfortable and keep you from developing another UTI: 

• Drink plenty of fluids to help flush bacteria out of your urinary system.

• Limit caffeine because it can make you dehydrated.

• Avoid sex while being treated for a UTI.

• Avoid tight-fitting pants.

• Wear cotton underwear.

• Don't soak in a bath for longer than 30 minutes in a day or more than twice a day.

• Take acetaminophen (Tylenol) to help with pain relief. When pregnant, do not take nonsteroidal anti-inflammatory drugs (NSAIDs), like ibuprofen (Advil, Motrin) and naproxen (Aleve). 

Can you take AZO while pregnant?

Yes. Phenazopyridine (AZO) is a medication that’s used to relieve UTI symptoms. It can help relieve feelings of burning, frequency, and urgency. In studies, phenazopyridine wasn’t linked to any birth defects. So it’s generally considered safe to use. It’s important to remember that this medication doesn’t cure the infection. But it can help you feel more comfortable.

Can a UTI during pregnancy harm a growing baby?

A UTI usually won’t harm your growing baby. But a UTI that isn’t treated properly with antibiotics can worsen and turn into a more severe infection — and this could result in problems for your baby, including:

• Preterm birth

• Low birth weight

• Infection

A UTI that isn’t treated properly can affect your health, too. Without prompt treatment, you’re at risk for developing:

• Pyelonephritis: If a UTI is allowed to grow beyond the bladder to the kidneys, it is called pyelonephritis. This complication is more likely to happen during pregnancy than at other times because of pressure on the bladder from the growing baby.

• Chorioamnionitis: This is an infection inside the uterus. It can happen when bacteria reach the amniotic fluid or the membranes that surround a developing baby, and it’s more likely to occur when there’s GBS bacteria in the urine.

• Preeclampsia: This dangerous condition can occur during the second half of pregnancy and often begins with high blood pressure and protein in the urine. There’s a strong link between UTI during pregnancy and preeclampsia.

Why trust our experts?

Written by:

Nicole E. Cieri-Hutcherson, PharmD, BCPS, NCMP

Nicole E. Cieri-Hutcherson, PharmD, BCPS, NCMP, has over a decade of experience as a pharmacist, professor, and researcher. She was a full-time clinical professor in the pharmacy practice department at D’Youville School of Pharmacy before subsequently joining the faculty of the pharmacy practice department at the University at Buffalo School of Pharmacy and Pharmaceutical Sciences.

Edited by:

Patricia Pinto-Garcia, MD, MPH

Patricia Pinto-Garcia, MD, MPH, is a medical editor at GoodRx. She is a licensed, board-certified pediatrician with more than a decade of experience in academic medicine.

Reviewed by:

Adriena Beatty D.O., MBA, CPE

Adriena Beatty, DO, MBA, CPE, is an Army veteran and board-certified obstetrician and gynecologist with over 20 years of experience. She is a graduate from Tuskegee University with a degree in chemical engineering and chemistry.

Our editorial standards

Meet our experts