What to Know About UTI and Pregnancy

Urinary tract infections (UTIs) are especially common during pregnancy. They are often caused by Escherichia coli (E. coli), bacteria that can cause diarrhea and other infections. When left untreated, UTIs can lead to issues with fertility as well as complications during and after pregnancy.

UTIs develop when bacteria enter the urethra (the thin tube that carries urine from the bladder out of the body) and infect the urinary tract. Complicated infections that aren't treated can affect reproductive organs, including the uterus.

UTIs and Fertility

While UTIs are not usually directly blamed for fertility problems, infertility has been linked to infections of the genital and urinary tracts. Most often, they are caused by sexually transmitted infections (STIs) such as chlamydia, but other infections can lead to inflammatory disease too, like prostatitis, inflammation of the prostate gland in men. They can affect the testes, epididymis (the duct behind the testis), and other glands, too.

These infections can result in infertility in several ways. They can damage sperm production, as well as sperm quality and function. They can also cause inflammation that blocks the reproductive tract.

In women, even though urine and reproductive fluids don't share the same passageways, bacteria can travel from the urethra to the vagina and enter the reproductive tract.

UTIs and Gestation

Urinary tract infections are common during pregnancy. Changes in anatomy and body chemistry contribute to this increased risk. In many cases, these infections develop with no symptoms, but they can still cause complications.

Risks

Pregnant people have a higher risk of developing UTIs starting at around the sixth week of gestation. The bladder becomes fuller later in pregnancy as well, and muscle tone can decrease. This causes urine to become stagnant and can even back up into the urinary tract, increasing the risk for infection.

Urine also changes during pregnancy, becoming more concentrated, with higher levels of estrogen and glucose that can help to feed bacteria and lower your body's defenses against infection.

Bacteria that commonly cause UTIs in pregnant women include:

• E. coli 
• Enterobacteriaceae, which can cause wound infections and meningitis
• Proteus mirabilis, which can lead to bladder and kidney infections
• Klebsiella pneumoniae, which can cause pneumonia and bloodstream infections

Bacteria like group B streptococcus and Staphylococcus saprophyticus less commonly cause UTIs, but group B can cause infections in the unborn baby and be passed on to your baby during delivery. Your doctor will usually test you for this type of bacteria before you give birth.

Treatment

If your UTI is diagnosed early, before it has spread to the kidneys—or even your blood—treatment with oral antibiotics, taken for about a week, is usually sufficient. The most common types of antibiotics used to treat UTIs in pregnancy include:

• Keflex (cephalexin)
• Erythromycin
• Augmentin (amoxicillin-clavulanic acid)
• Nitrofurantoin
• Bactrim (trimethoprim-sulfamethoxazole)

If your UTI is caused by group B streptococcus, your healthcare provider should start intravenous (IV, through a vein) antibiotic therapy in labor to prevent sepsis, a potentially life-threatening blood infection, in your baby.

Concerning Symptoms

Untreated urinary tract infections in pregnant women, even if they occur with no symptoms, can lead to kidney infections (pyelonephritis).

Symptoms of UTIs during pregnancy may include:

• Pain or burning with urination (dysuria)
• Urinary frequency or urinary urgency
• Suprapubic pain (pain in your lower abdomen) and tenderness
• Fever
• Chills
• Malaise (overall feeling of being unwell)
• Anorexia (lack or loss of appetite)
• Nausea and vomiting

UTI and Postpartum

A number of infections can occur in the postpartum period, and they affect 5%–24% of mothers. The most common postpartum infections are:

• Urinary tract infections
• Mastitis (inflammation and infection of breast tissue)
• Wound infections

UTIs are most common after a cesarean delivery (C-section). Vaginal births may seem like the riskier delivery type, but mothers who have C-sections typically have a urinary catheter placed to drain their bladder for at least a small period of time. What can develop is called a catheter-associated UTI that's caused by bacteria entering the urinary tract through the catheter.

Impact on Recovery

For the first few months of the postpartum period, your immune system is not yet working at full capacity. This means you could be more prone to developing infections, and your body won't be able to fight them as well as it normally would.

Other challenges of the postpartum period—like adjusting to a new normal, hormonal changes, and the physical demands of caring for a newborn—make this time less than ideal for illness. Infections that cause additional stress and discomfort could result in even more strain.

Breastfeeding

There are very few diseases that would prevent you from breastfeeding, and these are mostly viral diseases like human immunodeficiency virus (HIV) and AIDS. You are more likely to pass illness to your infant through respiratory contact while breastfeeding than through breast milk. Urinary tract infections cannot pass to the baby through your breast milk.

However, if you become severely ill with UTI complications like pyelonephritis or urosepsis (when untreated UTIs spread to your kidneys), how much milk you produce could be affected. Also, treatment with certain antibiotics or other medications could cause a concern since some drugs can cross over from your blood into your breast milk and be passed on to your baby.

Summary

UTIs are generally not linked to fertility issues unless they are frequent and untreated. UTIs are especially common during pregnancy because your ureter will expand to prepare for delivery, making it easier for bacteria to enter and cause an infection. Your risk of having UTIs remains high postpartum as well because your body is still recovering. Your healthcare team will keep a close eye on you and help treat your UTIs to make sure they don't cause complications for you and your baby.

A Word From Verywell

The changes that take place in your body during pregnancy can make it easy for bacteria to enter and grow, resulting in an increased risk of developing urinary tract infections. Many of these infections develop with no symptoms at all and can lead to complications for you and your baby.

Fortunately, your healthcare provider will screen for UTIs at the start of your pregnancy and before delivery. If you do develop a UTI, your medical team will treat it early so the infection doesn't spread to your kidneys. Only certain antibiotics are safe during pregnancy, and your healthcare provider will recommend one that won't harm you or the baby.

Frequently Asked Questions

What causes a UTI during pregnancy?

UTIs during pregnancy are caused by bacteria. The risk of developing a UTI increases in pregnancy due to changing anatomy and body chemistry.

How do you treat UTIs during pregnancy?

Antibiotics are used to treat urinary tract infections in both pregnant and nonpregnant women. Which antibiotics are used may be different, though, since not all antibiotics are safe during pregnancy.

When are UTIs common in pregnancy?

UTIs are most common in the second trimester of pregnancy, when your ureter begins to dilate, or expand, in preparation for delivery.

What does a UTI feel like when pregnant?

Many urinary tract infections during pregnancy develop with no symptoms. Symptoms that are present can include burning or pain during urination and urinary frequency or urgency. You may also have fever, chills, and pain and tenderness in your lower abdomen, below the pubic bone.