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Week 33 · Third Trimestermoderate

Urinary Tract Infection at 33 Weeks Pregnant

Urinary tract infections (UTIs) are more common in pregnancy due to hormonal and anatomical changes. They require prompt treatment with antibiotics to prevent progression to kidney infection (pyelonephritis), which can trigger preterm labor.

👶 What's Happening at Week 33

Your baby is now the size of a pineapple.

  • The pupils constrict and dilate in response to light.
  • Bones continue to harden (except the skull — it stays flexible for birth).
  • The immune system is developing with antibodies from the placenta.

🔬 Why You're Experiencing Urinary Tract Infection at Week 33

  • Progesterone relaxes the urinary tract walls, slowing urine flow and allowing bacteria to multiply
  • Growing uterus compresses the bladder, causing incomplete emptying
  • Glucose in the urine (more common in pregnancy) promotes bacterial growth
  • The shorter female urethra makes ascending infection easier
  • Asymptomatic bacteriuria (bacteria in urine without symptoms) affects 2–10% of pregnant women and must be treated

💊 Relief Tips for Week 33

1
Antibiotics (Prescribed)UTIs in pregnancy always require antibiotic treatment — do not leave them untreated. Your provider will choose a pregnancy-safe antibiotic.
2
Increase Fluid IntakeDrinking more water dilutes urine and helps flush bacteria from the bladder.
3
Urinate FrequentlyDon't hold urine for long periods. Urinate promptly when you feel the urge.
4
Wipe Front to BackProper hygiene after using the toilet prevents bacteria from the anal region from entering the urethra.
5
Urinate After IntercourseVoiding after sex helps flush bacteria that may have entered the urethra.

📋 Other Week 33 Symptoms

Waddling gaitOverheatingClumsinessPelvic pain (SPD)
See full Week 33 guide →

⚠️ Call Your Doctor If…

  • Burning or stinging when urinating
  • Frequent, urgent need to urinate with little output
  • Cloudy, dark, or strong-smelling urine
  • Blood in the urine (pink or red tinge)

Frequently Asked Questions

Are UTIs dangerous during pregnancy?

Untreated UTIs in pregnancy can progress to kidney infection (pyelonephritis), which is associated with preterm labor and sepsis. All UTIs in pregnancy must be treated promptly.

What antibiotics are safe for UTIs in pregnancy?

Nitrofurantoin, amoxicillin, cephalexin, and trimethoprim-sulfamethoxazole (with restrictions by trimester) are commonly used. Your provider will choose based on the bacteria found and trimester.

How is UTI diagnosed in pregnancy?

Urine culture (dipstick plus laboratory culture) is the standard test. Your provider will routinely screen for asymptomatic bacteriuria at your first prenatal visit.

What is asymptomatic bacteriuria?

Asymptomatic bacteriuria is bacteria detected in a urine culture without any symptoms. It is screened for at the first prenatal visit and treated in pregnancy because of the high risk of progression to kidney infection.

Medical Disclaimer: This content is for informational purposes only and does not constitute medical advice. Always consult your OB/GYN or midwife about symptoms during pregnancy.