title: Physiological range of human chorionic gonadotropin for support of early human pregnancy.
abstract: OBJECTIVE
  To determine the physiological range of hCG in early pregnancy.
  
  
  METHODS
  Retrospective study of patient charts.
  
  
  METHODS
  Magee-Women's Hospital IVF clinic, Monroeville, Pennsylvania.
  
  
  METHODS
  Sixty patients with successful, singleton birth outcomes.
  
  
  METHODS
  Serum hCG measurements on days 12-16 post-oocyte retrieval (OR).
  
  
  METHODS
  Lowest values, highest values, mean values, quartile mean values, and 48-hour doubling times for days 12-16 post-OR.
  
  
  RESULTS
  The average production of hCG in successful pregnancies is roughly 4-fold greater than the lowest amount observed in successful pregnancies, suggesting that a considerable excess of hCG is normally produced. Additionally, the average doubling time is almost 2-fold greater than the slowest doubling rate.
  
  
  CONCLUSIONS
  The data from this study provide a set of values for the minimum and maximum threshold of hCG for days 12-16 post-OR that may be physiologically required, although not entirely predictive, for a successful IVF pregnancy outcome.
authors.affiliation: Department of Obstetrics, Gynecology and Reproductive Sciences, Magee-Women's Research Institute, 204 Craft Avenue, Pittsburgh, Pennsylvania 15213, USA. rsicar@mail.magee.edu
authors.forename: C A
authors.initials: CA
authors.lastname: Richard
authors.forename: C J
authors.initials: CJ
authors.lastname: Kubik
authors.forename: J A
authors.initials: JA
authors.lastname: DeLoia
mesh_terms: D006063:Chorionic Gonadotropin / Q000097:blood*; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D011247:Pregnancy / Q000097:blood*; D011256:Pregnancy Outcome; D012189:Retrospective Studies; D013997:Time Factors; D020858:Tissue and Organ Harvesting
chemical_list: D006063:Chorionic Gonadotropin