title: Fetal exposure to tobacco: nicotine and cotinine concentration in amniotic fluid and maternal saliva.
abstract: OBJECTIVE
  Fetal exposure to tobacco constituents is a risk factor for negative birth outcomes. We aimed to determine the relationships between nicotine and cotinine concentrations in amniotic fluid and maternal saliva.
  
  
  METHODS
  As part of a therapeutic trial, 42 pregnant smokers agreed to sample amniotic fluid (8 samples from amniocentesis, 34 at birth). Their smoking characteristics were collected along with the newborns' birth outcomes.
  
  
  RESULTS
  The median concentrations [IQR] in amniotic fluid and saliva were 11 [7-31] and 38 [7-174] μg/L for nicotine and 72 [22-123] μg/L and 55 [17-109] μg/L for cotinine, respectively. Multivariate models showed that saliva cotinine concentration predicted amniotic fluid nicotine and cotinine concentrations (R2=0.398, p < 0.0001 and R2=0.708, p < 0.0001 respectively). Amniotic fluid nicotine or cotinine concentration was not associated with birth weight. In multivariate analysis, the time elapsed since the last cigarette was the only variable associated with increased birth weight (R2=0.237, p = 0.002).
  
  
  CONCLUSIONS
  Maternal saliva sampling for the determination of cotinine concentration is of interest to monitor fetal exposure to nicotine of any origin. Nevertheless, the time elapsed since the last cigarette was a better predictor of birth weight than the biomarkers' concentrations in amniotic fluid or maternal saliva.
authors.affiliation: a Département de Pharmacologie, Groupe Hospitalier Pitié-Salpêtrière, APHP , Paris , France and.
authors.forename: Nelly
authors.initials: N
authors.lastname: Jacob
authors.affiliation: b Département de Biostatistique, Groupe Hospitalier Pitié-Salpêtrière, APHP , Paris , France.
authors.forename: Jean-Louis
authors.initials: JL
authors.lastname: Golmard
authors.affiliation: a Département de Pharmacologie, Groupe Hospitalier Pitié-Salpêtrière, APHP , Paris , France and.
authors.forename: Ivan
authors.initials: I
authors.lastname: Berlin
mesh_terms: D000328:Adult; D000653:Amniotic Fluid / Q000737:chemistry*; D002853:Chromatography, Liquid; D003367:Cotinine / Q000302:isolation & purification*; D005260:Female; D006801:Humans; D016014:Linear Models; D008431:Maternal-Fetal Exchange; D009538:Nicotine / Q000302:isolation & purification*; D011247:Pregnancy; D012463:Saliva / Q000737:chemistry*; D012907:Smoking / Q000009:adverse effects*; D014028:Tobacco Smoke Pollution; D055815:Young Adult
chemical_list: D014028:Tobacco Smoke Pollution; D009538:Nicotine; D003367:Cotinine
keywords: Birth weight; maternal smoking during pregnancy; prenatal tobacco exposure