New Study May Lead to Better Probiotics for Bacterial Vaginosis in Pregnancy

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Bacterial vaginosis (BV) is the most common vaginal condition in young women of childbearing age. It is an unpleasant bacterial infection that causes vaginal discharge, itching, and burning. BV can increase the risk of sexually transmitted diseases (STDs). During pregnancy, BV has been linked to both low birthweight babies and premature birth. You can read about BV during pregnancy here.

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 and during pregnancy.

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. According to the CDC, about one million pregnant women get BV every year.

One of the big problems with BV is that it is hard to treat. The usual treatment is an antibiotic medication to kill off the bad bacteria, but BV comes back within 6 months in about half of all cases. A few years ago, I wrote a Pulse blog about using probiotics to treat BV during pregnancy. You can read that here.

Since that blog, oral probiotic supplements with LB have become commonly available to treat BV. Some studies show that these probiotics help and reduce recurrence, used or alone or with antibiotics. However, studies have not found strong and consistent benefits.

Now, a study from the University of Cape Town in South Africa suggests that an improved probiotic could improve BV treatment and reduce recurrence. It seems that probiotics really do work when the right species of bacteria is used in the probiotic.

The new study, published in the journal PLOS Pathogens, found that although commercial probiotics for BV do have LB species, they rarely match the LB species actually found in a woman’s vagina.

The investigators isolated 57 LB species from vaginal secretions of 26 young 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 most safe and 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 are 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.

Let your doctor know if you develop a strong vaginal odor, increased discharge, burning when passing urine, itching, or pain during sex. Treatment with an antibiotic may help reduce any pregnancy risks. Clinical trials are underway to find better, species-specific lactobacilli for probiotic supplements to treat BV. In the meantime, follow your doctor’s instructions for treatment. Ask  your doctor if you should add a probiotic or yogurt with lactobacillus. That may help for now. Better choices for probiotics may be coming soon.

Christopher Iliades
Dr. Chris Iliades is a medical doctor with 20 years of experience in clinical medicine and clinical research. Chris has been a full time medical writer and journalist since 2004. His byline appears in over 1,000 articles online including EverydayHealth, The Clinical Advisor, and Healthgrades. He has also written for print media including Cruising World Magazine, MD News, and The Johns Hopkins Children's Center Magazine. Chris lives with his wife and close to his three children and four grandchildren in the Boston area.

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