Variations in the vaginal bacterial flora: a preliminary report

Area of Science:

• Microbiology
• Gynecology
• Human Microbiome Studies

Background:

• The vaginal microbiome plays a crucial role in women's health.
• Understanding microbial dynamics throughout the menstrual cycle is essential.

Purpose of the Study:

• To investigate bacterial load and species diversity in vaginal samples during different menstrual cycle phases.
• To determine the prevalence of Staphylococcus aureus in various anatomical sites (nares, hands, vaginal vestibule, vagina) across the menstrual cycle.

Main Methods:

• Collected sequential vaginal, vestibule, nasal, and hand specimens from 14 women over three menstrual cycles.
• Performed qualitative and quantitative analyses on vaginal samples.
• Specifically tested all specimens for the presence of Staphylococcus aureus.

Main Results:

• Vaginal bacterial counts were highest premenstrually (approx. 10(9)/mL) but had the lowest species diversity (approx. 11).
• Menstrual samples showed the lowest bacterial counts (approx. 4.0 x 10(7)/mL) but highest species diversity (approx. 14).
• Staphylococcus aureus prevalence was highest in vaginal (64%) and nasal (57%) samples.

Conclusions:

• Bacterial composition in the vagina significantly varies with the menstrual cycle.
• Staphylococcus aureus is commonly found in the female genital tract and nares, suggesting potential transmission routes.