With Lactobacilli among the most prevalent microorganisms in vaginal commensal flora, it seems logical that probiotics can be used to help restore homeostasis. Their impact in BV or thrush is not clear cut, however. NICE says there is insufficient evidence, but adds that probiotics can be used and are unlikely to cause any harm.¹⁰ Others would point to increasing scientific support for probiotics in thrush, and intravaginal lactobacilli products are available.

North American researchers have demonstrated Lactobacilli spp can help restore health in women with BV, by helping indigenous levels recover.¹ Another study showed a greater improvement by introducing Lactobacillus intravaginally than with intravaginal metronidazole. Probiotics suppressed bacterial overgrowth, restoring homeostasis gradually and steadily, and having a more sustained effect.¹⁶

Oral administration of Lactobacilli is also effective, and can lengthen the period of remission in patients with recurrent BV.^1,17 A number of mechanisms of action could be at play, including:¹

• A lowering of pathogen ascension from the vagina
• Increased Lactobacilli transfer from the rectum to the vagina
• A transient disruption of the BV biofilm
• Immune-modulating effects helping indigenous Lactobacilli to recover.

Addressing pH balance, Bayer has launched Canesbalance, containing lactic acid and glycogen gel. The BNF says that: "Vaginal preparations intended to restore normal acidity may prevent recurrence of vaginal infections and permit the re-establishment of the normal vaginal flora." However, the use of intravaginal douches may also affect drug treatments, so advice should be given accordingly.¹²