During childbearing years, the normal vaginal biota is predominantly which organism?

During childbearing years, the normal vaginal biota is predominantly which organism?

• A. Enterococcus
• B. Lactobacillus
• C. Propionibacterium
• D. Coagulase-negative Staphylococcus

Answer: (B)

Dominance of Lactobacillus in the vagina during childbearing years is driven by hormonal effects that increase vaginal glycogen. Lactobacilli metabolize this glycogen to lactic acid, lowering the pH to around 4.0–4.5. This acidic environment inhibits many pathogens and helps maintain a stable, protective microbial community. Some lactobacilli also produce hydrogen peroxide, adding to antimicrobial defense. Other organisms listed are typically associated with the skin or gut and are not the main residents of a healthy, reproductive-age vaginal microbiota.

Dominance of Lactobacillus in the vagina during childbearing years is driven by hormonal effects that increase vaginal glycogen. Lactobacilli metabolize this glycogen to lactic acid, lowering the pH to around 4.0–4.5. This acidic environment inhibits many pathogens and helps maintain a stable, protective microbial community. Some lactobacilli also produce hydrogen peroxide, adding to antimicrobial defense. Other organisms listed are typically associated with the skin or gut and are not the main residents of a healthy, reproductive-age vaginal microbiota.