Bacterial vaginosis (BV) is the most common vaginal condition in women ages 15 to 44. Besides causing uncomfortable symptoms, BV can increase the risk of sexually transmitted diseases (STDs) and complications in pregnancy. A new study from University of Cape Town in South Africa suggests that an improved probiotic could improve BV treatment and reduce risks and complications.

BV occurs when the normal “good” bacteria that live in the vagina, called Lactobacillus (LB),  get overwhelmed by “harmful” bacteria species. Why this balance shifts is not known, but it is more common in women who are sexually active.

When LB are the dominant bacteria, they keep the acidity of the vagina high, which inhibits the growth of harmful bacteria. When the balance shifts to harmful bacteria, symptoms of BV develop, including vaginal discharge, odor, itching and burning.

The usual treatment is antibiotics, but BV comes back within six months in about half of all cases. Oral probiotic supplements for BV have been used to replace LB and improve treatment. Some studies show that probiotics help and reduce recurrence, alone or with antibiotics. However, studies have not found strong and consistent benefits.

The new study, published in the journal PLOS Pathogens, found that although the commercial probiotics for BV have LB species, they rarely match the species actually found in a woman’s vagina. The investigators isolated 57 LB species from vaginal secretions of 26 women. These LB species were compared to the LB species from available commercial probiotics. In a laboratory match up, actual LB species were much more effective at increasing vaginal acidity (lowering the pH) and inhibiting growth of harmful bacteria.

Five of the natural LB species were the safest and most effective. They were also resistant to metronidazole, a common antibiotic used to treat BV. This is important because they could be used along with the antibiotic and remain viable as the harmful bacteria were killed.

The researchers would like to see further studies that lead to development of new and better probiotics using the natural LB species. They believe this type of probiotic would be more reliable and could reduce BV complications of pregnancy like low birthweight babies and premature birth. It would also reduce STDs, including a reduction in the risk for HIV.

Source: Study titled “Exploring Potential of Vaginal Lactobacillus Isolates From South African Women for Enhancing Treatment for Bacterial Vaginosis,” by researchers at University of Cape Town, South Africa, published in PLOS Pathogens.