title: [Serum estradiol the day of hCG administration as predictor factor of IVF-ET].
abstract: BACKGROUND
  Since the beginning of assisted reproductive technologies, they have been in search of a pregnancy predictor, mainly in in vitro fertilization, due to its difficulty and expensiveness.
  
  
  OBJECTIVE
  To know if there is an optimal estradiol levels to reach pregnancy in patients with in vitro fertilization and embryo transference.
  
  
  METHODS
  Retrospective and descriptive study of 179 patients in the fresh in vitro fertilization cycles from January 1 to December 31,2006. Patients were grouped by serum estradiol level the day before of hCG administration: Group 1, < 1,000; Group 2, 1,001-1,500; Group 3, 1,501-2,000; Group 4, 2,001-2,500; Group 5, 2,501-3,000, and Group 6, > 3,000 pg/dL. Pearson's chi-square and ANOVA, with Stata, were used to determine whether E2 levels were associated with oocyte number, quality, maturation and pregnancy rates.
  
  
  RESULTS
  A significant difference was noted in the number of MII oocytes retrieved and pregnancy rates, but there is no relation with E2 levels. Higher pregnancy rate was at Group 1, where older patients were too.
  
  
  CONCLUSIONS
  Estradiol level before hCG administration is not a predictor factor of pregnancy rates, nor even determinant of oocyte retrieval cancellation in patients with in vitro fertilization and embryo transference, mostly in advanced age patients.
authors.affiliation: Centro Especializado para la Atención de la Mujer, Unidad de Reproducción Asistida, Hospital Angeles de las Lomas, México.
authors.forename: Alberto
authors.initials: A
authors.lastname: Kably Ambe
authors.forename: Sergio
authors.initials: S
authors.lastname: Estévez González
authors.forename: Esperanza
authors.initials: E
authors.lastname: Carballo Mondragón
mesh_terms: D000328:Adult; D006063:Chorionic Gonadotropin / Q000008:administration & dosage*; D004624:Embryo Transfer; D004958:Estradiol / Q000097:blood*; D005260:Female; D005307:Fertilization in Vitro; D006801:Humans; D011379:Prognosis; D012189:Retrospective Studies
chemical_list: D006063:Chorionic Gonadotropin; D004958:Estradiol