Group B Streptococcus and E. coli Are Primary Causes of UTIs During Pregnancy
The correct answer is A. UTI - Group B Streptococcus and E. coli are the two leading bacterial pathogens causing urinary tract infections during pregnancy. 1, 2
Primary Pathogens in Pregnancy-Related UTIs
- E. coli is the most common pathogen causing both symptomatic and asymptomatic urinary tract infections in pregnant women 2
- E. coli is specifically identified as the second-leading bacterial cause of neonatal sepsis (after GBS), but remains the predominant uropathogens in maternal UTIs 1
- Group B Streptococcus causes 2-4% of urinary tract infections during pregnancy and is clinically significant because GBS bacteriuria in any concentration indicates heavy genital tract colonization 1
Clinical Significance of GBS Bacteriuria
- Any quantity of GBS detected in urine during pregnancy requires intrapartum chemoprophylaxis, as it serves as a surrogate marker for heavy maternal colonization and increased risk of neonatal disease 1
- GBS bacteriuria is associated with higher risk for early-onset neonatal GBS disease compared to simple colonization 1
- Symptomatic GBS urinary tract infections should be diagnosed and treated according to current standards of care, though screening cultures at 35-37 weeks are not necessary for women with documented GBS bacteriuria 1
Prevalence and Impact
- Urinary tract infections affect 2-15% of pregnant women overall, making them the most common bacterial infection during pregnancy 3, 2
- Asymptomatic bacteriuria affects 2-7% of pregnant women and requires treatment during pregnancy (unlike in non-pregnant patients) to prevent complications 3
- Untreated asymptomatic bacteriuria progresses to acute pyelonephritis in up to 30% of cases, with associated risks of preterm birth, low birth weight, and preeclampsia 2