title: Concentrations of soluble Fas in maternal serum and amniotic fluid during uncomplicated pregnancies.
abstract: OBJECTIVE
  To determine, during normal pregnancy, maternal serum (MS) and amniotic fluid (AF) concentrations of soluble Fas (sFas), an apoptosis-suppressing molecule that might play a role in the apoptotic process. Soluble Fas levels might explain existing immunotolerance, fetal well being, and rupture of membranes at term.
  
  
  METHODS
  Sixty-six healthy, nonsmoking, pregnant women (mean age 32.6 +/- 4.8 years) with uncomplicated singleton pregnancies (15 in the first trimester, 30 in the second trimester, and 21 at term vaginal delivery) and 20 healthy nonpregnant women (mean age 32.5 +/- 3.8 years) were included in the study.
  
  
  RESULTS
  MS and AF sFas concentrations were measured by a sandwich enzyme-linked immunosorbent assay, and parametric tests were used in the statistical analysis.MS and AF sFas concentrations significantly depended on gestational age (P < .0008 and P < .0002, respectively). MS concentrations were significantly lower in the first trimester than those in the second trimester (P <.003), those at term (P < .03), and those in nonpregnant controls (P < .005). AF concentrations decreased significantly at term compared with those in the second trimester (P < .0003). AF sFas concentrations in the second trimester and at term were significantly lower than respective MS concentrations (P < .00001).
  
  
  CONCLUSIONS
  MS sFas concentrations decreased significantly in the first trimester of pregnancy, possibly affecting semiallograft tolerance. In the second trimester, concentrations return to control levels and remain unchanged until delivery. AF sFas concentrations decrease at term compared with the second trimester, possibly indicating increased apoptosis in preparation for rupture of membranes.
authors.affiliation: 2nd Department of Obstetrics and Gynaecology, University of Athens, Athens, Greece. geocre@aretaieio.uoa.gr
authors.forename: Ariadne
authors.initials: A
authors.lastname: Malamitsi-Puchner
authors.forename: Angeliki
authors.initials: A
authors.lastname: Sarandakou
authors.forename: Vasiliki
authors.initials: V
authors.lastname: Papagianni
authors.forename: Efthimia
authors.initials: E
authors.lastname: Protonotariou
authors.forename: John
authors.initials: J
authors.lastname: Tziotis
authors.forename: Dimitrios
authors.initials: D
authors.lastname: Botsis
mesh_terms: D000328:Adult; D000653:Amniotic Fluid / Q000737:chemistry*; D017209:Apoptosis; D005260:Female; D005865:Gestational Age; D006801:Humans; D011247:Pregnancy; D012016:Reference Values; D019014:fas Receptor / Q000032:analysis* / Q000097:blood*
chemical_list: D019014:fas Receptor