1, Pregnancy: The incidence is higher in the third trimester when estrogen levels are highest after placenta formation than in late pregnancy. 2.Oral contraceptives and estrogen: Oral contraceptives with high estrogen levels lead to an increase in the rate of Pseudomonas vaginalis colonization. 3, Diabetes: Increased blood glucose levels in vaginal tissues encourage fungal adhesion and growth. Vaginal epithelial cells have a greater tendency to bind Pseudomonas aeruginosa. 4. Application of antimicrobial drugs: It is possible that antimicrobial drugs induce a reduction in Lactobacillus, thus contributing to the overgrowth of pseudofilamentous yeast. 5. Application of adrenocorticotropin: long application time or large amount leads to decrease in immune function of the body; causes dysbiosis, and pseudofilamentous yeast is easy to grow and reproduce and cause disease. 6. Irrigation and feminine hygiene products: Irrigation can cause the risk of VVC by reducing the amount of Lactobacillus in the vagina. 7. Other possible factors: such as impermeable clothing, iron deficiency, feminine hygiene products, chemical exposure, local allergy or highly sensitive reaction, sexual behavior.