Can estrogen vaginal therapy cause a yeast infection?

Vaginal Estrogen Therapy and Yeast Infections

Vaginal estrogen therapy does not increase the risk of yeast infections (vulvovaginal candidiasis) and is considered safe for treating vaginal atrophy in postmenopausal women. 1

Relationship Between Estrogen and Yeast Infections

• Vaginal estrogen therapy has not been shown to increase the risk of urinary tract infections or yeast infections 1
• The American Urological Association, Canadian Urological Association, and Society of Urodynamics, Female Pelvic Medicine & Urogenital Reconstruction guidelines specifically state that vaginal estrogen therapy has minimal systemic risks due to low absorption 1
• Vaginal estrogen therapy is recommended for peri- and post-menopausal women with recurrent urinary tract infections to reduce future UTI risk 1

Biological Mechanisms

• While laboratory studies show that estrogen can promote Candida albicans colonization in experimental settings, this does not translate to clinical evidence of increased yeast infections with vaginal estrogen therapy 2, 3
• Research indicates that estrogen may affect how Candida interacts with the immune system, but clinical guidelines do not identify vaginal estrogen as a risk factor for yeast infections 4
• Estrogen actually helps restore normal vaginal flora with lactobacilli dominance, which can help prevent pathogenic bacterial colonization 1

Clinical Considerations

• Vulvovaginal candidiasis (VVC) is caused by Candida albicans or occasionally other Candida species and affects approximately 75% of women at least once in their lifetime 1
• Common symptoms of yeast infections include pruritus (itching), vaginal discharge, soreness, burning, dyspareunia, and external dysuria 1
• Diagnosis is made through clinical symptoms plus either microscopic identification of yeast/pseudohyphae or positive culture 1
• Yeast infections are associated with a normal vaginal pH (≤4.5), which is actually promoted by healthy estrogen levels 1

Treatment Options for Yeast Infections

• If a yeast infection does occur (regardless of cause), treatment options include:
  • Topical azole medications (more effective than nystatin) 1
  • Oral fluconazole 150 mg as a single dose 1
  • For recurrent infections, maintenance therapy may be required 5

Special Considerations

• For postmenopausal women using vaginal estrogen who develop a yeast infection, the same treatment approach as for younger women should be used 5
• Oral antifungal medications may be more acceptable for older women due to ease of administration 5
• Women with recurrent vulvovaginal candidiasis who have had hysterectomies may be more prone to harbor resistant fungi species, requiring more aggressive treatment 6

Practical Recommendations

• When prescribing vaginal estrogen therapy, reassure patients that it does not increase risk of yeast infections 1
• For women with vaginal atrophy symptoms, a stepwise approach is recommended:
  • Start with lubricants and vaginal moisturizers
  • If symptoms persist, low-dose vaginal estrogen can be safely used 1
• Vaginal estrogen preparations come in various forms including creams, tablets, and rings, all of which are effective for treating vaginal atrophy 1