Urinary tract infections (UTIs) are far more than a minor discomfort—they can pose serious health risks for both mother and child if left untreated. Affecting parts of the urinary system such as the kidneys, bladder, ureters, and urethra, UTIs are particularly prevalent in women, who are roughly 50 times more likely than men to experience them. Pregnancy amplifies that risk due to physiological changes that favor bacterial colonization, typically by Escherichia coli. Metabolic and hormonal shifts, along with other vaginal infections like recurrent candidiasis, further contribute to vulnerability.
Why UTIs Matter During Pregnancy
Left unchecked, UTIs can trigger severe complications, including maternal sepsis, which threatens the life of both mother and baby. While infections can arise at any stage of pregnancy, they are most common in the second half of gestation. According to gynecologist Bárbara Murayama, UTIs manifest in three primary forms:
Types of Urinary Tract Infections
1. Asymptomatic Bacteriuria
This occurs when bacteria are present in the urine without producing any noticeable symptoms.
2. Cystitis
A lower urinary tract infection affecting the bladder, cystitis occurs in roughly 1–2% of pregnant women. All people with a vagina are susceptible due to anatomical factors, such as the short distance between urethra and anus.
3. Pyelonephritis
This upper urinary tract infection happens when bacteria travel up the ureters to the kidneys, often causing back pain and discomfort during urination. Most cases appear during the second and third trimesters.
Risks for Mother and Baby
Untreated UTIs during pregnancy are linked to premature birth, low birth weight, and perinatal mortality. Bacteria can spread to the kidneys, potentially escalating to maternal sepsis. Low immunity, which naturally occurs during pregnancy, further increases susceptibility. Lilian Fiorelli, a gynecologist specializing in female sexuality and urogynecology at the University of São Paulo, highlights additional risk factors:
- Gestational diabetes
- Diarrhea
- Recurrent vaginal infections such as candidiasis
- Hormonal changes
- Pelvic floor dysfunction
- Kidney stones
Recognizing the Symptoms
Symptoms vary, and some pregnant women may show none at all. Common signs mirror those in non-pregnant individuals:
- Pain or burning sensation when urinating
- Frequent, sudden urges to urinate in small volumes
- Abdominal discomfort or a sense of pressure
- Dark, foul-smelling urine, possibly with blood
- Persistent low-grade fever
“The immune system during pregnancy is somewhat compromised, which can mask symptoms and allow potentially severe infections to develop,” explains Fiorelli. Even common pregnancy sensations—like frequent urination or bladder pressure—can obscure the presence of a UTI.
Diagnosing UTIs in Pregnancy
Diagnosis relies on laboratory urine culture (uroculture) to confirm infection and identify the responsible microorganism. Results take roughly three days. In the interim, a standard urinalysis can indicate elevated leukocytes or the presence of nitrites—bacterial byproducts—but only an antibiogram can specify the optimal antibiotic treatment. Regular testing, ideally monthly or whenever symptoms appear, is recommended to catch infections early.
Treatment Protocols
Antibiotics, such as cephalexin, remain the cornerstone of treatment, typically prescribed for seven to fourteen days. Pregnant women are also advised to maintain hydration, avoid holding urine, and empty the bladder completely during each visit to the bathroom. In cases of recurrent infection, low-dose daily antibiotic prophylaxis may continue until delivery. Severe cases may require hospitalization and further testing, as Murayama notes.
Home Remedies and Limitations
No home remedy alone can effectively treat a UTI during pregnancy. While certain teas may relieve symptoms, they must complement—not replace—antibiotic therapy and should be cleared with a healthcare professional to avoid pregnancy complications.
Prevention Strategies
Prevention focuses on managing risk factors, particularly low immunity. Recommended habits include:
- Drinking plenty of water to flush bacteria
- Addressing any existing genital infections or constipation
- Proper genital hygiene after urination
- Urinating soon after sexual intercourse
- Avoiding perfumed products in the genital area
- Wearing loose-fitting clothing
- Using cotton underwear and changing it daily
UTIs during pregnancy are common but far from trivial. With timely diagnosis, effective treatment, and preventive practices, the risks to both mother and child can be significantly reduced. Awareness and vigilance remain the most powerful tools for safeguarding maternal and fetal health.
