title: Vaginal lactobacilli and preterm birth.
abstract: OBJECTIVE
  To assess the relationship between the absence of vaginal lactobacilli and preterm birth at < 33 weeks of gestation.
  
  
  METHODS
  A prospective study of the vaginal flora in the second trimester was undertaken in 1958 women with singleton pregnancies. The contribution of various microorganisms to preterm delivery was analyzed using a multivariate-logistic regression model.
  
  
  RESULTS
  Lactobacillus species were not cultured from 28% of 118 women who delivered at < 33 weeks, 10% of 224 women who delivered between 33 and 36 weeks, and 5% of 1616 women who delivered at > 37 weeks of gestation. Lactobacilli (odds ratio and 95% confidence interval: 0.15 [0.09 to 0.24]), Mycoplasma hominis (2.3 [1.0 to 5.4]), and glucose non-fermentative gram-negative rods (2.1 [1.0 to 4.2]) were identified as independent risk factors for preterm delivery at < 33 weeks of gestation. Absence of lactobacilli (sensitivity and positive predictive value: 28% and 25%) was a better predictor of preterm delivery at < 33 weeks of gestation than the presence of Mycoplasma hominis (7% and 13%, respectively) or glucose non-fermentative rods (9% and 11%).
  
  
  CONCLUSIONS
  Although this was not a cohort study, results suggest that tests for determining the presence of vaginal lactobacilli may be clinically useful tools for identifying women at an increased risk of preterm delivery at < 33 weeks of gestation.
authors.affiliation: Department of Obstetrics and Gynecology, Jichi Medical School, Tochigi.
authors.forename: Rie
authors.initials: R
authors.lastname: Usui
authors.forename: Akihide
authors.initials: A
authors.lastname: Ohkuchi
authors.forename: Shigeki
authors.initials: S
authors.lastname: Matsubara
authors.forename: Akio
authors.initials: A
authors.lastname: Izumi
authors.forename: Takashi
authors.initials: T
authors.lastname: Watanabe
authors.forename: Mitsuaki
authors.initials: M
authors.lastname: Suzuki
authors.forename: Hisanori
authors.initials: H
authors.lastname: Minakami
mesh_terms: D000328:Adult; D004926:Escherichia coli / Q000302:isolation & purification; D005260:Female; D005865:Gestational Age; D006801:Humans; D007564:Japan / Q000453:epidemiology; D007778:Lactobacillus / Q000302:isolation & purification*; D009174:Mycoplasma / Q000302:isolation & purification; D007752:Obstetric Labor, Premature / Q000175:diagnosis* / Q000453:epidemiology / Q000209:etiology; D011237:Predictive Value of Tests; D011247:Pregnancy; D011262:Pregnancy Trimester, Second; D011446:Prospective Studies; D012680:Sensitivity and Specificity; D014621:Vagina / Q000382:microbiology*