A randomised controlled trial of probiotics for the prevention of spontaneous preterm delivery associated with bacterial vaginosis: preliminary results

摘要

Background Bacterial vaginosis increases the risk of spontaneous preterm delivery at less than 34 weeks of gestation. Objective The purpose of this study was to evaluate the efficacy of the early administration of selected lactobacilli strains (probiotics) to pregnant women with asymptomatic bacterial vaginosis/intermediate-degree infections to prevent spontaneous premature delivery and associated neonatal morbidity. Methods/Design Asymptomatic pregnant women at less than 20 weeks of gestation, with no indication of elective preterm delivery, with a vaginal pH ≥ 4.5 and Nugent score > 3 were randomly assigned to the placebo or intervention group (oral administration of selected lactobacilli up to the 24th to 26th week of gestation). The randomisation was stratified for the history of premature delivery (HPD) and blocked. The allocation was concealed, and the participating health professionals and patients were blinded. The primary outcome was preterm delivery ( Results In total, 4,204 pregnant women were screened; 320 and 324 individuals were respectively randomly assigned to the placebo and intervention groups, and 62% finished the trial. None of the randomised patients were lost to follow-up. For the non-HPD stratum, the intent-to-treat relative risks of spontaneous premature birth at Conclusions The efficacy of the tested probiotics to prevent preterm delivery among women without a history of preterm delivery was not determined because the study sample was insufficient to estimate statistically significant intent-to-treat effects; additional studies are needed to evaluate this intervention among these women. Trial registration Trial registration at NIH register: NCT00303082 . Sources of funding: the Brazilian Health Ministry and the State of Rio de Janeiro Research Foundation.