What is a urinary tract infection?

A urinary tract infection (UTI) is an infection of the urinary system. UTIs are the most common bacterial infection that women develop during pregnancy. They can occur in different parts of the urinary tract, including the bladder (cystitis), urethra (urethritis) or kidneys (pyelonephritis). Sometimes when a UTI develops and bacteria are detected in the urinary tract, you may not have any symptoms of an infection. This is known as asymptomatic bacteriuria.

While anyone can get a UTI, they are much more common in women than men and they are also more likely to occur in the very young and the elderly.

What are the symptoms of UTIs during pregnancy?

Common symptoms of a UTI during pregnancy are similar to those that you might experience at any other time, and include:

• a burning sensation when you pass urine
• feeling the urge to urinate more often than usual
• urinating before you reach the toilet (‘leaking’ or incontinence)
• feeling like your bladder is full, even after you have urinated
• urine that looks cloudy, bloody or is very smelly
• pain above the pubic bone
• fever

Sometimes the first sign of an infection is a faint prickly sensation when you pass urine. If the infection is more advanced and has moved up to the kidneys, you may also experience fever with a particularly high temperature, back pain and vomiting.

What are the common causes of UTIs?

Your urinary tract is normally free of bacteria. If bacteria enter the tract and multiply, they can cause a UTI. There are several factors that increase the risk of developing an infection:

• Infection with common bacteria in your gut, usually from faeces (poo) can contaminate your urinary tract
• Being sexually active increases the risk of bacteria moving around the genital area and entering the urinary tract
• If you have weak pelvic floor muscles your bladder might not empty completely, which can lead to an infection
• Women with diabetes are at increased risk of developing a UTI since the sugar in their urine may cause bacteria to multiply

Are UTIs a risk during pregnancy?

During pregnancy, many changes occur in your body that increase your risk of developing a UTI, including changes to the make-up of your urine and immune system. As your baby grows, there is also an increase in the pressure on your bladder, which can reduce the flow of your urine and lead to an infection.

UTIs can affect women whether they are pregnant or not. However, pregnant women are more likely to develop repeated or more severe infections. Up to 1 in 10 pregnant women will have a UTI but not have any symptoms at all.

Is there a risk to my baby?

Having a UTI during pregnancy can increase your risk of developing high blood pressure, and your baby may be born early and smaller than usual. For this reason, even if you don’t have any symptoms, it is important to treat a UTI as soon as possible.

How are UTIs diagnosed?

UTIs are diagnosed by taking a urine sample which is checked in a laboratory for bacteria. Your doctor may also perform a physical examination if they think you have an infection.

All pregnant women are offered a urine test, usually at their first antenatal visit or soon after. You may need to repeat the urine test if you have a history of UTIs; have symptoms of a UTI; have a contaminated sample or if your doctor thinks you are at high risk of developing a UTI. If you have frequent UTIs, you may also need additional tests such as an ultrasound of your kidneys.

How are UTIs treated during pregnancy?

When you have a UTI, it is important to drink plenty of water to flush out the urinary tract. UTIs are treated with antibiotics that are safe in pregnancy. Your doctor will select the right antibiotic, based on your infection and the type of bacteria found in your urine sample.

Can I prevent UTIs?

You can lower your risk of developing a UTI during pregnancy by:

• drinking plenty of fluids, especially water
• quickly treating any vaginal infection that may occur, including thrush or a sexually transmitted infection
• avoiding becoming constipated

Some women have also found the following tips helpful:

• urinate immediately after sex
• don’t delay going to the toilet — go as soon as you feel the need
• wipe from the front to the back after going to the toilet
• wear cotton underwear

When should I see my doctor?

See your midwife or doctor if you have any symptoms of a UTI. It’s important not to delay treatment since infections develop quickly, and can affect both you and your baby.

More information

UTIs are very common during pregnancy, and are best treated early. If you notice the symptoms of an infection, seek medical advice from your doctor, midwife or pharmacist.

For more information on UTIs, visit the Kidney Health Australia page on UTIs.