Why bacterial balance matters in BV
Bacterial vaginosis (BV) is a shift in the vaginal community: protective bacteria become less dominant while other bacteria multiply. It is not simply an infection caused by one germ. Standard treatment can reduce the bacteria associated with BV, but it may not rebuild the community that helps keep them in check. That helps explain why symptoms can return after treatment.
The role of Lactobacillus crispatus
Lactobacillus crispatus produces lactic acid, which helps keep the vagina’s pH—the measure of how acidic an environment is—low. Many BV-associated bacteria grow more readily when that environment becomes less acidic. A strong presence of L. crispatus may therefore make it harder for them to regain ground.
The idea behind restoring the bacterium is to support a more protective community, rather than only removing bacteria during an episode. But getting a helpful microbe to establish itself is not as simple as adding it once: it must persist amid the existing microbial community and the conditions that allowed BV to recur.
Why restoration is still being studied
Researchers are investigating ways to reintroduce L. crispatus and determine whether it can reduce recurrence. The key question is not just whether the bacterium is present soon after an intervention, but whether it remains there and helps maintain a healthier balance over time. If that proves possible, treatment could address the conditions that let BV return—not merely the latest episode.
