title: Low plasma levels of hCG after 10,000-IU hCG injection do not reduce the number or maturation of oocytes recovered in patients undergoing assisted reproduction.
abstract: OBJECTIVE
  Our purpose was to determine whether there is a correlation between human chorionic gonadotropin (hCG) blood levels and oocyte maturation.
  
  
  METHODS
  Three samples of blood were obtained at different times from hCG administration as follows: 12 hr, 36 hr, during oocyte recovery, and at 84 hr, when the patient comes for embryo transfer.
  
  
  RESULTS
  A total of 5036 oocytes was retrieved from 404 patients prospectively recruited between April 1996 and March 1997. The percentage of metaphase-II oocytes at different blood levels ranged from 84 to 88%. The general trend does not show any significant increase in percentage of metaphase-II oocytes in association with an increasing serum hCG concentration.
  
  
  CONCLUSIONS
  The results of this study suggest that at 12, 36, and 84 hr after hCG administration, levels as low as 50, 45, and 9 IU/L of hCG, respectively, are equally potent as higher levels at initiating maximal oocyte maturity.
authors.affiliation: Nottingham University Research and Treatment Unit in Reproduction (NURTURE), Department of Obstetrics & Gynaecology, UK.
authors.forename: S
authors.initials: S
authors.lastname: al-Hassan
authors.forename: S
authors.initials: S
authors.lastname: Fishel
authors.forename: S
authors.initials: S
authors.lastname: Fleming
authors.forename: S
authors.initials: S
authors.lastname: Thornton
mesh_terms: D000328:Adult; D002064:Buserelin / Q000008:administration & dosage; D006063:Chorionic Gonadotropin / Q000008:administration & dosage / Q000097:blood / Q000493:pharmacokinetics* / Q000494:pharmacology; D004305:Dose-Response Relationship, Drug; D005260:Female; D005307:Fertilization in Vitro; D007987:Gonadotropin-Releasing Hormone / Q000819:agonists; D006801:Humans; D008596:Menotropins / Q000008:administration & dosage; D009866:Oogenesis / Q000187:drug effects*; D011446:Prospective Studies
chemical_list: D006063:Chorionic Gonadotropin; D007987:Gonadotropin-Releasing Hormone; D008596:Menotropins; D002064:Buserelin