The relationship between acute inflammatory lesions of the preterm placenta and amniotic fluid microbiology

Am J Obstet Gynecol. 1992 May;166(5):1382-8. doi: 10.1016/0002-9378(92)91609-e.


Objective: Our objective was to determine the relationship between microbial invasion of the amniotic cavity and the presence and severity of acute inflammatory lesions in the placenta.

Study design: Placental histologic and amniotic fluid microbiologic studies were performed in 92 consecutive patients who were admitted with preterm labor and intact membranes and delivered within 48 hours after amniocentesis.

Results: The prevalence of a positive amniotic fluid culture was 38% (35 of 92). There was a strong association between the presence and severity of inflammation in the amnion, chorion-decidua, umbilical cord, and chorionic plate and the results of the amniotic fluid culture (p less than 0.0001 for each tissue section). Three patterns of inflammation of the chorion-decidua were identified: marginating, nonmarginating, and a mixed pattern. The marginating and the mixed patterns of inflammation were strongly associated with the presence of a positive amniotic fluid culture. Acute inflammation of the chorionic plate was the most sensitive indicator of a microbial invasion of the amniotic cavity (sensitivity 96.6%), and funisitis and umbilical vasculitis had the highest specificity (85.7%).

Conclusion: The presence of acute inflammatory lesions of the chorioamniotic membranes can serve as a marker of microbial invasion of the amniotic cavity.

Publication types

  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Amnion / microbiology
  • Amnion / pathology
  • Amniotic Fluid / microbiology*
  • Bacteria / isolation & purification
  • Chorioamnionitis / microbiology
  • Chorioamnionitis / pathology
  • Chorion / microbiology
  • Chorion / pathology
  • Decidua / microbiology
  • Decidua / pathology
  • Female
  • Humans
  • Inflammation / microbiology*
  • Placenta Diseases / microbiology*
  • Placenta Diseases / pathology
  • Pregnancy
  • Pregnancy Complications / microbiology*
  • Umbilical Cord / microbiology
  • Umbilical Cord / pathology