The most common cause of vaginal discharge in women of childbearing age is bacterial vaginosis, which is characterized by a complex change in the vaginal flora with a reduction of lactobacilli and an increase in anaerobic bacteria such as Gardnerella vaginalis.
Among women with bacterial vaginosis (BV), 50%-75% are asymptomatic. Symptomatic women usually present with vaginal odor and/or discharge that is off-white, thin, and homogeneous in most cases. BV can create complications in pregnancy, but up to half of cases resolve spontaneously. Treatment is usually with antibiotics, but BV will recur in 69% of women within 1 year. Other than treatment with antibiotics, are there alternative ways to manage this disease?
Both oral and vaginal delivery of lactobacilli are known to renew vaginal microbiota. But is oral lactobacillus alone effective for treating BV?
Vujic et al. conducted a double-blind, randomized, placebo-controlled clinical trial evaluating the efficacy of a probiotic containing lactobacilli for the treatment of women with BV (Eur. J. Obstet. Gynecol. Reprod. Biol. 2013;168:75-9). Women were eligible for inclusion if they were older than 18 years of age and diagnosed with vaginal infection including BV, candidiasis, trichomoniasis, or a combination of these conditions. Women were excluded if they were pregnant, lactating, or menstruating. Subjects received either two capsules containing greater than 1 x 109 CFU lactobacillus daily or matching placebo for 6 weeks. At 6 and 12 weeks after randomization, subjects underwent gynecologic examinations for a wet mount evaluation and recovery of vaginal flora on agar plates. The primary outcome of the study was the rate of restitution of normal vaginal microbiota at 6 weeks.
In all, 544 subjects were randomized (395 to probiotic and 149 to placebo). Adherence to medication was greater than 90% in both groups. Restitution of balanced vaginal microbiota was evident in 243 subjects (61.5%) in the probiotic group and 40 subjects (26.9%) in the placebo group (P less than .001). At 12 weeks, normal vaginal microbiota was present in 51% of subjects in the probiotic group but only 21% of subjects taking placebo (P less than .001). The number-needed-to-treat was 2.9 with a relative risk reduction of 47.4% at 6 weeks.
For nonpregnant women with mild symptoms, the use of oral probiotics may be a reasonable option. For women who have recurrent episodes of BV, data suggest that probiotics could prevent future episodes, but more data is needed to evaluate this hypothesis.
Dr. Ebbert is professor of medicine and a general internist at the Mayo Clinic in Rochester, Minn. The opinions expressed are those of the author.