title: Premature labor: a state of platelet activation?
abstract: OBJECTIVE
  This study was undertaken to determine whether premature labor is associated with changes in the maternal plasma concentration of soluble CD40 ligand (sCD40L), a marker of platelet activation.
  
  
  METHODS
  A cross-sectional study included patients in the following groups: 1) non-pregnant (n=21); 2) normal pregnancy (n=71); 3) normal pregnancy at term with (n=67) and without labor (n=88); 4) preterm labor (PTL) with intact membranes (n=136) that was divided into the following sub-groups: 4a) PTL who delivered at term (n=49); 4b) PTL without intra-amniotic infection and/or inflammation (IAI) who delivered preterm (n=54); and 4c) PTL with IAI who delivered preterm (n=33). sCD40L concentrations were measured by ELISA.
  
  
  RESULTS
  The median maternal plasma sCD40L concentration was higher in pregnant than non-pregnant women (P=0.017). Patients with PTL had a higher median maternal plasma sCD40L concentration than women with normal pregnancies, regardless of the presence or absence of IAI and gestational age at delivery (P<0.001 for all comparisons). IAI was not associated with a higher median maternal plasma concentration of sCD40L.
  
  
  CONCLUSIONS
  Normal pregnancy is a state in which there is a physiologic increase of sCD40L. PTL was associated with an increased median maternal plasma sCD40L concentration that could not be accounted for by IAI. Thus, our findings suggest that platelet activation occurs during an episode of preterm labor.
authors.affiliation: Perinatology Research Branch, NICHD/NIH/DHHS, Bethesda, MD 20892, USA.
authors.forename: Offer
authors.initials: O
authors.lastname: Erez
authors.forename: Roberto
authors.initials: R
authors.lastname: Romero
authors.forename: Debra
authors.initials: D
authors.lastname: Hoppensteadt
authors.forename: Jawed
authors.initials: J
authors.lastname: Fareed
authors.forename: Tinnakorn
authors.initials: T
authors.lastname: Chaiworapongsa
authors.forename: Juan Pedro
authors.initials: JP
authors.lastname: Kusanovic
authors.forename: Shali
authors.initials: S
authors.lastname: Mazaki-Tovi
authors.forename: Francesca
authors.initials: F
authors.lastname: Gotsch
authors.forename: Nandor Gabor
authors.initials: NG
authors.lastname: Than
authors.forename: Edi
authors.initials: E
authors.lastname: Vaisbuch
authors.forename: Chong Jai
authors.initials: CJ
authors.lastname: Kim
authors.forename: Jimmy
authors.initials: J
authors.lastname: Espinoza
authors.forename: Pooja
authors.initials: P
authors.lastname: Mittal
authors.forename: Neil
authors.initials: N
authors.lastname: Hamill
authors.forename: Chia-Ling
authors.initials: CL
authors.lastname: Nhan-Chang
authors.forename: Moshe
authors.initials: M
authors.lastname: Mazor
authors.forename: Sonia
authors.initials: S
authors.lastname: Hassan
mesh_terms: D000293:Adolescent; D000328:Adult; D015415:Biomarkers / Q000097:blood; D023201:CD40 Ligand / Q000097:blood*; D002821:Chorioamnionitis / Q000097:blood; D003430:Cross-Sectional Studies; D005260:Female; D006801:Humans; D007752:Obstetric Labor, Premature / Q000097:blood*; D015539:Platelet Activation; D011247:Pregnancy; D011251:Pregnancy Complications, Infectious / Q000097:blood; D055815:Young Adult
chemical_list: D015415:Biomarkers; D023201:CD40 Ligand