Probiotics to prevent vulvovaginal infections in symptomatic pregnant women with normal vaginal flora-multicenter double-blind, randomized, placebo-controlled study

During pregnancy, abnormal vaginal flora (AVF), bacterial vaginosis (BV) and vulvovaginal candidiasis (VVC) are associated with serious complications and discomfort. We aimed to elucidate the effectiveness of oral probiotics in primary prevention of BV/AVF and VVC in pregnant women. A multicenter prospective randomized, double blind, placebo controlled trial was conducted at three medical centers between 2016 and 2021. Women who complaint on vaginal symptoms with negative smear for AVF/BV or candida were divided into a research group, receiving 2 capsules/day of oral probiotic formula containing Bifidobacteriumbifidum, Bifidobacteriumlactis, Lactobacillus (L) acidophilus, L. paracasei, L. rhamnosus and Streptococcus thermophilus ( >6X109/capsule), and a control group, receiving a placebo (2 capsules/day) until delivery. At least once a month and following complaints a vaginal smear was taken to assess vaginal flora. If positive, BV/AVF or VVC were treated with antibiotics or antimycotic agent, respectively. Eradication was assessed by a repeated vaginal smear. Vaginal colonization with the specific bacteria from the probiotic capsules was detected using the matrix-assisted laser desorption/ionization time-of-flight mass spectrometry (MALDI TOF-MS).The primary outcome was the rate of women who developed any vaginal infection (BV/AVF/VVC) during the study period until delivery. Assuming 15% rate of vaginal infection in the treatment group versus 40% in the placebo group, 98 women were required (80% power, 5% two-sided alpha). Forty-nine and 51 women were analyzed in the treatment and placebo cohorts, respectively. Baseline characteristics are presented in table 1. There was no difference in the rate of any vulvovaginal infection between the cohorts: 14 (29%) versus 14 (27%) in the treatment and placebo groups, respectively (P=0.8) (table 2). No woman had vaginal colonization with bacteria from the probiotic capsule. The oral probiotic product tested in this study did not reduce the rate of vulvovaginal infections in pregnant women with normal vaginal flora.View Large Image Figure ViewerDownload Hi-res image Download (PPT)