Can estrogen cream be used to prevent Urinary Tract Infections (UTIs)?

Vaginal Estrogen Cream for UTI Prevention in Postmenopausal Women

Topical vaginal estrogen is strongly recommended for the prevention of recurrent urinary tract infections (UTIs) in postmenopausal women. 1

Mechanism and Effectiveness

• Menopause causes a reduction in vaginal estrogen, leading to increased vaginal pH and alteration in vaginal microbiota away from the protective lactobacillus-dominant environment 1
• The vagina becomes more readily colonized by gram-negative uropathogens, increasing UTI risk 1
• Topical estrogen therapy:
  • Reduces vaginal pH 1
  • Reduces gram-negative bacterial colonization 1
  • Restores protective lactobacillus 1, 2
  • Significantly decreases recurrence of UTIs 1, 3
  • Modulates the genitourinary inflammatory profile, with decreased cell shedding and reduced inflammatory markers 2

Evidence Supporting Vaginal Estrogen

• Meta-analyses show that vaginal estrogen prevents recurrent UTIs in postmenopausal women 1
• A 2021 randomized clinical trial demonstrated that commonly prescribed forms of vaginal estrogen with contemporary dosing schedules prevent UTIs in postmenopausal women with recurrent UTIs 3
• Higher efficacy is associated with weekly doses of ≥850 μg 4
• In one study, the incidence of UTI was significantly reduced in the estrogen group compared to the antibiotic group (2/27 vs 12/15, p<0.001) 5

Important Distinctions

• Topical (vaginal) estrogen is effective, while systemic (oral) estrogen does not reduce recurrent UTIs 1, 4
• Available forms include vaginal creams, pessaries, rings, or vaginal tablets 4, 3

Safety Considerations

• Patient confusion regarding safety of vaginal estrogen is common but unfounded 1
• Data do not show increased risk of:
  • Recurrence of breast cancer 1
  • Endometrial hyperplasia 1
  • Endometrial carcinoma 1
• This is because there is no associated increase in serum estrogen levels 1
• Recent evidence supports using vaginal estrogen therapy even for breast cancer patients with genitourinary symptoms when nonhormonal treatments fail 1

Potential Limitations

• May be associated with vaginal irritation and poor adherence in some patients 1
• Should be used as part of a comprehensive approach to UTI prevention 1

Algorithm for UTI Prevention in Postmenopausal Women

1. Confirm diagnosis of recurrent UTIs (>2 culture-positive UTIs in 6 months or >3 in one year) 1
2. Initiate vaginal estrogen therapy as first-line non-antimicrobial prevention 1
3. Consider adding lactobacillus-containing probiotics 1
4. If vaginal estrogen alone is insufficient:
   • Consider methenamine hippurate (1g twice daily) 1
   • Reserve antimicrobial prophylaxis for when non-antimicrobial interventions have failed 1

By following this evidence-based approach, recurrent UTIs can be effectively managed in postmenopausal women while minimizing antibiotic use and its associated risks of resistance and adverse effects.