title: Fetal-placental inflammation, but not adrenal activation, is associated with extreme preterm delivery.
abstract: OBJECTIVE
  Spontaneous labor at term involves the activation of placental corticotropin-releasing hormone and the fetal adrenal axis, but the basis for extreme preterm labor is unknown. Our objective was to determine whether placental corticotropin-releasing hormone is activated in extreme preterm labor.
  
  
  METHODS
  One thousand five hundred six mothers delivering at less than 28 weeks' gestation were enrolled. Each mother/infant pair was assigned to the category that described the primary reason for hospitalization. Observers who had no knowledge of patient categorization assessed placenta microbiology, histology, and corticotropin-releasing hormone expression. These were correlated with the primary reason for hospitalization.
  
  
  RESULTS
  Among infants delivered at less than 28 weeks' gestation, spontaneous (vs induced) delivery was associated with less placental corticotropin-releasing hormone expression and more frequent signs of placental inflammation and infection.
  
  
  CONCLUSIONS
  Inflammation and infection, rather than premature activation of the fetal adrenal axis, should be the major focus of research to prevent extremely preterm human birth.
authors.affiliation: Division of Endocrinology, Department of Medicine, Children's Hospital Boston, Harvard Medical School, Boston, MA 02115, USA.
authors.forename: Sunita
authors.initials: S
authors.lastname: Trivedi
authors.forename: Maria
authors.initials: M
authors.lastname: Joachim
authors.forename: Thomas
authors.initials: T
authors.lastname: McElrath
authors.forename: Harvey J
authors.initials: HJ
authors.lastname: Kliman
authors.forename: Elizabeth N
authors.initials: EN
authors.lastname: Allred
authors.forename: Raina N
authors.initials: RN
authors.lastname: Fichorova
authors.forename: Andrew
authors.initials: A
authors.lastname: Onderdonk
authors.forename: Fernanda
authors.initials: F
authors.lastname: Heitor
authors.forename: Leila
authors.initials: L
authors.lastname: Chaychi
authors.forename: Alan
authors.initials: A
authors.lastname: Leviton
authors.forename: Joseph A
authors.initials: JA
authors.lastname: Majzoub
mesh_terms: D000311:Adrenal Glands / Q000378:metabolism; D002821:Chorioamnionitis / Q000382:microbiology*; D015331:Cohort Studies; D003346:Corticotropin-Releasing Hormone / Q000032:analysis; D016207:Cytokines / Q000097:blood; D005260:Female; D006801:Humans; D007231:Infant, Newborn; D008297:Male; D015337:Multicenter Studies as Topic; D010920:Placenta / Q000737:chemistry / Q000166:cytology / Q000382:microbiology; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000382:microbiology*; D011256:Pregnancy Outcome; D047928:Premature Birth / Q000382:microbiology*
chemical_list: D016207:Cytokines; D003346:Corticotropin-Releasing Hormone