The goal of this observational study is to explore a standardized sample process for improving the accuracy of vaginal microbiota evaluation and to explore a more complete and comprehensive method for vaginal microbiota evaluation based on gram staining.

This study consists of two sub-studies:

1. Sub-study on Standardized method of Microscopic Slide Preparation: this sub-study aims to compare different slide preparation methods and dilution levels based on various aspects, including uniformity, impurities, clarity and so on, and then explore the optimal method and dilution level. Additionally, it will summarize the conversion method for white blood cells between wet mount and gram staining, and for white blood cells between high-power microscopy and oil immersion microscopy.
2. Sub-study on Vaginal Microbiota Evaluation on Gram Staining: For patients with diagnosed vaginal infection type, it will calculate the consistency of results between different laboratories. And it will evaluate the effectiveness combined artificial intelligence technology and other technological platforms. Besides, for patients without diagnosed vaginal infection type, different methods such as 16S rRNA gene sequencing and metagenomic sequencing are used for analysis and profiling to guide treatment.

Inclusion Criteria:

• Non-pregnant women who visit our research settings and conduct vaginal discharge examination based on Gram-stained smear.
• No sexual intercourse, vaginal douching, or vaginal medication within the last 72 hours.
• Not during menstruation (menstrual period ended ≥3 days ago).

exclusion Criteria:

• Receiving systemic or vaginal antifungal or antibiotic treatment within the past week.

VENUS study plans to enrol 5590 participants, aged 15-49 years, from visiting our research settings across the country who evaluate vaginal discharge based on Gram-stained smear.