Identification of intracellular bacteria in the basal plate of the human placenta in term and preterm gestations

Published:January 21, 2013DOI:


      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.

      Study Design

      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.


      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.


      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.

      Key words

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        • Gibbs R.S.
        • Romero R.
        • Hillier S.L.
        • Eschenbach D.A.
        • Sweet R.L.
        A review of premature birth and subclinical infection.
        Am J Obstet Gynecol. 1992; 166: 1515-1528
        • Romero R.
        • Sirtori M.
        • Oyarzun E.
        • et al.
        Infection and labor, V: prevalence, microbiology, and clinical significance of intraamniotic infection in women with preterm labor and intact membranes.
        Am J Obstet Gynecol. 1989; 161: 817-824
        • Romero R.
        • Schaudinn C.
        • Kusanovic J.P.
        • et al.
        Detection of a microbial biofilm in intraamniotic infection.
        Am J Obstet Gynecol. 2008; 198: 135.e1-135.e5
        • Schieve L.A.
        • Handler A.
        • Hershow R.
        • Persky V.
        • Davis F.
        Urinary tract infection during pregnancy: its association with maternal morbidity and perinatal outcome.
        Am J Public Health. 1994; 84: 405-410
        • Goldenberg R.L.
        • Andrews W.W.
        • Faye-Petersen O.
        • Cliver S.
        • Goepfert A.R.
        • Hauth J.C.
        The Alabama preterm birth project: placental histology in recurrent spontaneous and indicated preterm birth.
        Am J Obstet Gynecol. 2006; 195: 792-796
        • Carey J.C.
        • Klebanoff M.A.
        • Hauth J.C.
        • et al.
        Metronidazole to prevent preterm delivery in pregnant women with asymptomatic bacterial vaginosis: National Institute of Child Health and Human Development Network of Maternal-Fetal Medicine Units.
        N Engl J Med. 2000; 342: 534-540
        • Klebanoff M.A.
        • Carey J.C.
        • Hauth J.C.
        • et al.
        Failure of metronidazole to prevent preterm delivery among pregnant women with asymptomatic Trichomonas vaginalis infection.
        N Engl J Med. 2001; 345: 487-493
        • McDonald H.M.
        • Brocklehurst P.
        • Gordon A.
        Antibiotics for treating bacterial vaginosis in pregnancy.
        Cochrane Database Syst Rev. 2007; 1 (CD000262)
        • Mysorekar I.U.
        • Hultgren S.J.
        Mechanisms of uropathogenic Escherichia coli persistence and eradication from the urinary tract.
        Proc Natl Acad Sci U S A. 2006; 103: 14170-14175
        • McElrath T.F.
        • Hecht J.L.
        • Dammann O.
        • et al.
        Pregnancy disorders that lead to delivery before the 28th week of gestation: an epidemiologic approach to classification.
        Am J Epidemiol. 2008; 168: 980-989
        • Leviton A.
        • Allred E.N.
        • Kuban K.C.
        • et al.
        Microbiologic and histologic characteristics of the extremely preterm infant's placenta predict white matter damage and later cerebral palsy: the ELGAN study.
        Pediatr Res. 2010; 67: 95-101
        • Fichorova R.N.
        • Onderdonk A.B.
        • Yamamoto H.
        • et al.
        Maternal microbe-specific modulation of inflammatory response in extremely low-gestational-age newborns.
        MBio. 2011; 2 (e00280-10)
        • Mayhew T.M.
        Stereology and the placenta: where's the point?.
        Placenta. 2006; 27: S17-S25
        • Mayhew T.M.
        Taking tissue samples from the placenta: an illustration of principles and strategies.
        Placenta. 2008; 29: 1-14
        • Ananth C.V.
        • Getahun D.
        • Peltier M.R.
        • Salihu H.M.
        • Vintzileos A.M.
        Recurrence of spontaneous versus medically indicated preterm birth.
        Am J Obstet Gynecol. 2006; 195: 643-650
        • Kim Y.M.
        • Bujold E.
        • Chaiworapongsa T.
        • et al.
        Failure of physiologic transformation of the spiral arteries in patients with preterm labor and intact membranes.
        Am J Obstet Gynecol. 2003; 189: 1063-1069
        • Kim Y.M.
        • Chaiworapongsa T.
        • Gomez R.
        • et al.
        Failure of physiologic transformation of the spiral arteries in the placental bed in preterm premature rupture of membranes.
        Am J Obstet Gynecol. 2002; 187: 1137-1142
        • McNutt L.A.
        • Wu C.
        • Xue X.
        • Hafner J.P.
        Estimating the relative risk in cohort studies and clinical trials of common outcomes.
        Am J Epidemiol. 2003; 157: 940-943
        • Muglia L.J.
        • Katz M.
        The enigma of spontaneous preterm birth.
        N Engl J Med. 2010; 362: 529-535
        • DiGiulio D.B.
        • Romero R.
        • Amogan H.P.
        • et al.
        Microbial prevalence, diversity and abundance in amniotic fluid during preterm labor: a molecular and culture-based investigation.
        PLoS One. 2008; 3: e3056
        • Onderdonk A.B.
        • Delaney M.L.
        • DuBois A.M.
        • Allred E.N.
        • Leviton A.
        Detection of bacteria in placental tissues obtained from extremely low gestational age neonates.
        Am J Obstet Gynecol. 2008; 198: 110.e1-110.e7
        • Roberts D.J.
        • Celi A.C.
        • Riley L.E.
        • et al.
        Acute histologic chorioamnionitis at term: nearly always noninfectious.
        PLoS One. 2012; 7: e31819
        • Strunk T.
        • Doherty D.
        • Jacques A.
        • et al.
        Histologic chorioamnionitis is associated with reduced risk of late-onset sepsis in preterm infants.
        Pediatrics. 2012; 129: e134-e141
        • Lee J.
        • Romero R.
        • Dong Z.
        • et al.
        Unexplained fetal death has a biological signature of maternal anti-fetal rejection: chronic chorioamnionitis and alloimmune anti-human leucocyte antigen antibodies.
        Histopathology. 2011; 59: 928-938
        • Xu Y.
        • Tarquini F.
        • Romero R.
        • et al.
        Peripheral CD300a+CD8+ T lymphocytes with a distinct cytotoxic molecular signature increase in pregnant women with chronic chorioamnionitis.
        Am J Reprod Immunol. 2012; 67: 184-197
        • Russo T.A.
        • Stapleton A.
        • Wenderoth S.
        • Hooton T.M.
        • Stamm W.E.
        Chromosomal restriction fragment length polymorphism analysis of Escherichia coli strains causing recurrent urinary tract infections in young women.
        J Infect Dis. 1995; 172: 440-445
        • Brauner A.
        • Jacobson S.H.
        • Kuhn I.
        Urinary Escherichia coli causing recurrent infections–a prospective follow-up of biochemical phenotypes.
        Clin Nephrol. 1992; 38: 318-323
        • Foxman B.
        • Zhang L.
        • Tallman P.
        • et al.
        Virulence characteristics of Escherichia coli causing first urinary tract infection predict risk of second infection.
        J Infect Dis. 1995; 172: 1536-1541
        • Elliott T.S.
        • Reed L.
        • Slack R.C.
        • Bishop M.C.
        Bacteriology and ultrastructure of the bladder in patients with urinary tract infections.
        J Infect. 1985; 11: 191-199
        • Andrews W.W.
        • Goldenberg R.L.
        • Hauth J.C.
        • Cliver S.P.
        • Conner M.
        • Goepfert A.R.
        Endometrial microbial colonization and plasma cell endometritis after spontaneous or indicated preterm versus term delivery.
        Am J Obstet Gynecol. 2005; 193: 739-745
        • Onderdonk A.B.
        • Hecht J.L.
        • McElrath T.F.
        • Delaney M.L.
        • Allred E.N.
        • Leviton A.
        Colonization of second-trimester placenta parenchyma.
        Am J Obstet Gynecol. 2008; 199: 52.e1-52.e10
        • Carr-Hill R.A.
        • Hall M.H.
        The repetition of spontaneous preterm labor.
        Br J Obstet Gynaecol. 1985; 92: 921-928
        • Goldenberg R.L.
        • Andrews W.W.
        • Hauth J.C.
        Choriodecidual infection and preterm birth.
        Nutr Rev. 2002; 60: S19-S25
        • Romero R.
        • Espinoza J.
        • Goncalves L.F.
        • Kusanovic J.P.
        • Friel L.
        • Hassan S.
        The role of inflammation and infection in preterm birth.
        Semin Reprod Med. 2007; 25: 21-39
        • Zeldovich V.B.
        • Robbins J.R.
        • Kapidzic M.
        • Lauer P.
        • Bakardjiev A.I.
        Invasive extravillous trophoblasts restrict intracellular growth and spread of Listeria monocytogenes.
        PLoS Pathog. 2011; 7: e1002005
        • Lecuit M.
        • Nelson D.M.
        • Smith S.D.
        • et al.
        Targeting and crossing of the human maternofetal barrier by Listeria monocytogenes: role of internalin interaction with trophoblast E-cadherin.
        Proc Natl Acad Sci U S A. 2004; 101: 6152-6157
        • Wu X.R.
        • Sun T.T.
        • Medina J.J.
        In vitro binding of type 1-fimbriated Escherichia coli to uroplakins Ia and Ib: relation to urinary tract infections.
        Proc Natl Acad Sci U S A. 1996; 93: 9630-9635
        • Watts D.H.
        • Krohn M.A.
        • Hillier S.L.
        • Eschenbach D.A.
        The association of occult amniotic fluid infection with gestational age and neonatal outcome among women in preterm labor.
        Obstet Gynecol. 1992; 79: 351-357
        • Hecht J.L.
        • Onderdonk A.
        • Delaney M.
        • et al.
        Characterization of chorioamnionitis in 2nd-trimester C-section placentas and correlation with microorganism recovery from subamniotic tissues.
        Pediatr Dev Pathol. 2008; 11: 15-22
        • Jones H.E.
        • Harris K.A.
        • Azizia M.
        • et al.
        Differing prevalence and diversity of bacterial species in fetal membranes from very preterm and term labor.
        PLoS One. 2009; 4: e8205
        • Barczak A.K.
        • Gomez J.E.
        • Kaufmann B.B.
        • et al.
        RNA signatures allow rapid identification of pathogens and antibiotic susceptibilities.
        Proc Natl Acad Sci U S A. 2012; 109: 6217-6222
        • Jefferson K.K.
        The bacterial etiology of preterm birth.
        Adv Appl Microbiol. 2012; 80: 1-22