BACTERIAL VAGINOSIS IS ASSOCIATED WITH PREMATURITY AND VAGINAL FLUID MUCINASE AND SIALIDASE - RESULTS OF A CONTROLLED TRIAL OF TOPICAL CLINDAMYCIN CREAM

OBJECTIVE: The pathogenesis of preterm birth and other adverse pregnan cy outcomes linked with reproductive tract infection remains poorly un derstood. Mucolytic enzymes, including mucinases and sialidases (neura minidase), are recognized virulence factors among enteropathogens and bacteria that cause periodontal infection. Perturbation of maternal ce rvicovaginal mucosal membrane host defenses by such enzyme-producing m icroorganisms may increase the risk of subclinical intrauterine infect ion during pregnancy and thus increase risks of preterm birth. STUDY D ESIGN: We prospectively evaluated vaginal fluid mucinase and sialidase and selected cervicovaginal bacteria along with pregnancy outcomes in 271 women. Within this study, women with bacterial vaginosis (16 to 2 7 weeks' gestation) were treated with 2% clinadmycin vaginal cream or placebo. Enzyme; microbial findings, treatment effects, and pregnancy outcomes were compared among drug- and placebo-treated women and contr ol women without bacterial vaginosis. RESULTS: Presence of bacterial v aginosis at intake was associated with increased risk of preterm birth (relative risk 3.3, 95% confidence interval 1.2 to 9.1, p = 0.02), pr emature rupture of membranes (relative risk 3.8, 95% confidence interv al 1.6 to 9.0, p = 0.002), and preterm premature rupture of membranes. Mucinase and sialidase activities were more commonly identified, and they occurred in higher concentrations, if present, in women with bact erial vaginosis (mucinase: 44.3% with bacterial vaginosis vs 27.4% wit hout, p = 0.007; sialidase: 45% with bacterial vaginosis vs 12% withou t, p < 0.001). Sialidase activity was associated with bacterial vagino sis-linked organisms (Gardnerella vaginalis, Mobiluncus spp, and Mycop lasma hominis) and Chlamydia trachomatis and yeast species; mucinase a ctivity was associated only with bacterial vaginosis-linked microorgan isms. Clindamycin, 2% cream, was effective treatment for bacterial vag inosis and temporarily reduced mucinase and sialidase activities. Topi cal treatment of bacterial vaginosis did not reduce risks of perinatal morbidity. Women with persistent or recurrent sialidase 8 weeks after treatment were at increased risk of preterm birth (15.6% vs 7.4%) pre mature rupture of membranes (30% vs 15%), and low birth weight (20% vs 3%, relative risk 6.8, 95% confidence interval 1.6 to 28.1). CONCLUSI ONS: Persistence of sialidase-producing vaginal microorganisms in numb ers sufficient to increase vaginal fluid sialidase activity may be a r isk factor for possibly preventable subclinical intrauterine infection and preterm birth. This study confirms and further informs our unders tanding of the association of bacterial vaginosis and preterm birth; s tudies to evaluate whether systemic treatment for bacterial vaginosis can effectively reduce vaginal mucolytic enzymes and risks of prematur ity and other morbid outcomes are continuing.