title: A prospective study of early pregnancy loss in humans.
abstract: OBJECTIVE
  To test two hypotheses: In spontaneous conceptions, early pregnancy loss (EPL) is associated with [1] inadequate luteal (ovarian) P, and/or [2] elevated follicular (adrenal) P.
  
  
  METHODS
  A population-based prospective study.
  
  
  METHODS
  Thirty rural Bolivian communities.
  
  
  METHODS
  Women volunteers (n = 191), 19-40 years old, in stable sexual unions and not using contraception.
  
  
  METHODS
  Collection of serial saliva samples throughout sequential ovarian cycles and urine samples during late luteal phases. Collections continued throughout pregnancy for each detected conception.
  
  
  METHODS
  Occurrence of spontaneous conceptions and subsequent outcomes. Salivary concentrations of P. Test for elevated urinary human chorionic gonadotropin (hCG).
  
  
  RESULTS
  Luteal (through implantation) P levels were similar in pregnancies lost within 5 weeks after conception (EPL; n = 8) and those pregnancies that were maintained longer (sustained conceptions, SC; n = 32). Follicular P was significantly higher in EPL than in SC.
  
  
  CONCLUSIONS
  [1] Elevated follicular P was associated with EPL in natural conceptions in healthy women. [2] Early pregnancy loss exhibits absolute luteal P levels comparable to SC, but lower luteal/follicular P ratios.
authors.affiliation: Anthropology Department, Indiana University, Bloomington, Indiana 47405, USA. Vitzthum@indiana.edu
authors.forename: Virginia J
authors.initials: VJ
authors.lastname: Vitzthum
authors.forename: Hilde
authors.initials: H
authors.lastname: Spielvogel
authors.forename: Jonathan
authors.initials: J
authors.lastname: Thornburg
authors.forename: Brady
authors.initials: B
authors.lastname: West
mesh_terms: D000022:Abortion, Spontaneous / Q000209:etiology*; D000328:Adult; D001942:Breast Feeding; D016022:Case-Control Studies; D005260:Female; D005498:Follicular Phase / Q000378:metabolism*; D006801:Humans; D008183:Luteal Phase / Q000378:metabolism*; D008423:Maternal Age; D011247:Pregnancy; D011261:Pregnancy Trimester, First; D011374:Progesterone / Q000378:metabolism*; D011446:Prospective Studies; D012463:Saliva / Q000378:metabolism*
chemical_list: D011374:Progesterone