title: Is salivary estriol detectable in very early pregnancy?
abstract: OBJECTIVE
  Estriol (E3) is produced by the placenta and is important for early pregnancy maintenance. In blood, E3 can be detected from the 8th week of pregnancy. Under the influence of the hypothalamic-pituitary-adrenal (HPA) axis hormone ACTH, E3 levels increase sharply after the 10th week. Although E3 can be reliably analyzed in saliva, till now information about the concentrations during the first trimester is missing. The aim of this study was to verify whether the sensitivity of a newly developed enzyme immunoassay is sufficient for the determination of salivary E3 (sE3) in very early pregnancy.
  
  
  METHODS
  Saliva samples were collected at home, once weekly in 25 healthy pregnant women from the 6th week of gestation to the end of the first trimester.
  
  
  RESULTS
  sE3 was detectable from the beginning of the 6th pregnancy week (M = 3.17 pg/ml, SD = 2.13). A steep significant increase between the 7th and the 8th week (p = 0.029) and again between the 10th and the 11th week (p = 0.001) was apparent.
  
  
  CONCLUSIONS
  Low concentrations of sE3 can be measured during very early pregnancy and may serve as a promising, easily assessable marker for future research on the mechanisms of healthy pregnancy.
authors.affiliation: a Department of Clinical Psychology and Psychotherapy , University of Zurich , Zurich , Switzerland and.
authors.forename: Manuela
authors.initials: M
authors.lastname: Wingeier
authors.affiliation: a Department of Clinical Psychology and Psychotherapy , University of Zurich , Zurich , Switzerland and.
authors.forename: Pearl
authors.initials: P
authors.lastname: La Marca-Ghaemmaghami
authors.affiliation: b Department of Obstetrics , University Hospital of Zurich , Zurich , Switzerland.
authors.forename: Roland
authors.initials: R
authors.lastname: Zimmermann
authors.affiliation: a Department of Clinical Psychology and Psychotherapy , University of Zurich , Zurich , Switzerland and.
authors.forename: Ulrike
authors.initials: U
authors.lastname: Ehlert
mesh_terms: D000328:Adult; D004964:Estriol / Q000032:analysis*; D005260:Female; D006801:Humans; D007124:Immunoenzyme Techniques / Q000379:methods*; D010865:Pilot Projects; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D012463:Saliva / Q000737:chemistry*; D012680:Sensitivity and Specificity
chemical_list: D004964:Estriol
keywords: Estriol; early pregnancy; salivary estriol