title: Identification of intracellular bacteria in the basal plate of the human placenta in term and preterm gestations.
abstract: OBJECTIVE
  Bacteria have been identified in different regions of the placenta. Here, we tested the hypothesis that the maternal basal plate of the placenta harbors microbes that may be associated with adverse pregnancy outcomes.
  
  
  METHODS
  We performed a cross-sectional study of pregnancies from a single tertiary care hospital. Maternal medical and obstetric characteristics were obtained and pregnancies followed up prospectively for outcomes and placental collection. After delivery, systematic random sampling of the placental basal plate was performed. Paraffin sections of basal plates were stained with 4 histologic stains and scored for morphological evidence of bacteria.
  
  
  RESULTS
  Of 195 total patients in the study, Gram-positive and -negative intracellular bacteria of diverse morphologies were documented in the basal plates of 27% of all placentas. Of the patients, 35% delivered preterm. No difference was noted between placental basal plates from preterm or term gestations. Intracellular bacteria were found in the placental basal plates of 54% spontaneous preterm deliveries <28 weeks, and in 26% of term spontaneous deliveries (P = .02). Intracellular bacteria were also documented in placentas without clinical or pathologic chorioamnionitis.
  
  
  CONCLUSIONS
  A total of 27% of placentas demonstrated intracellular bacteria in the placental basal plate using morphological techniques. Thus, the maternal basal plate is a possible source of intrauterine colonization and placental pathological examination could include examination for bacteria in this important maternal-fetal interface.
authors: Department of Obstetrics and Gynecology, Washington University School of Medicine, St. Louis, MO 63110, USA.
authors: Molly J
authors: MJ
authors: Stout
authors: Bridget
authors: B
authors: Conlon
authors: Michele
authors: M
authors: Landeau
authors: Iris
authors: I
authors: Lee
authors: Carolyn
authors: C
authors: Bower
authors: Qiuhong
authors: Q
authors: Zhao
authors: Kimberly A
authors: KA
authors: Roehl
authors: D Michael
authors: DM
authors: Nelson
authors: George A
authors: GA
authors: Macones
authors: Indira U
authors: IU
authors: Mysorekar
mesh_terms: D000328:Adult; D001419:Bacteria / Q000302:isolation & purification*; D002821:Chorioamnionitis / Q000382:microbiology* / Q000473:pathology; D003430:Cross-Sectional Studies; D005260:Female; D005865:Gestational Age; D006801:Humans; D008423:Maternal Age; D010920:Placenta / Q000382:microbiology* / Q000473:pathology; D011247:Pregnancy; D047928:Premature Birth / Q000382:microbiology* / Q000473:pathology