title: Low serum estradiol concentrations after five days of controlled ovarian hyperstimulation for in vitro fertilization are associated with poor outcome.
abstract: OBJECTIVE
  To evaluate the prognostic significance of low serum E2 concentrations in controlled ovarian hyperstimulation (COH) cycles for IVF.
  
  
  METHODS
  Retrospective study.
  
  
  METHODS
  Assisted conception unit of a university hospital.
  
  
  METHODS
  One thousand four hundred and forty patients undergoing COH for IVF.
  
  
  METHODS
  COH, serum E2 measurement, ultrasonographic scanning of ovarian follicles, oocyte retrieval, and ET.
  
  
  METHODS
  Cancellation and pregnancy rates.
  
  
  RESULTS
  Patients were classified into four groups according to serum E2 levels on the sixth day of COH: group A (E2 level < 50 pg/mL [114 cycles]), group B (E2 level 51-100 pg/mL [189 cycles]), group C (E2 level 101-200 pg/mL [320 cycles]), and group D (E2 level >200 pg/mL [817 cycles]). Group A experienced the highest cancellation rates (65.1%) and lowest pregnancy rates (7.8%) despite requiring significantly more hMG ampules (47.8+/-1.7). The cancellation rate was higher (75.1%) and no pregnancy occurred in a subset of group A in whom COH was initiated with > or =3 ampules (225 IU) of gonadotropins.
  
  
  CONCLUSIONS
  In COH cycles using luteal phase buserelin, low initial serum E2 concentrations are associated with poor outcome.
authors.affiliation: Guy's and St. Thomas' Assisted Conception Unit, St. Thomas' Hospital, London, United Kingdom. y.khalaf@umds.ac.uk
authors.forename: Y
authors.initials: Y
authors.lastname: Khalaf
authors.forename: A
authors.initials: A
authors.lastname: Taylor
authors.forename: P
authors.initials: P
authors.lastname: Braude
mesh_terms: D006063:Chorionic Gonadotropin / Q000627:therapeutic use; D004958:Estradiol / Q000097:blood*; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D005498:Follicular Phase; D006801:Humans; D008596:Menotropins / Q000627:therapeutic use; D017063:Outcome Assessment, Health Care; D010062:Ovulation Induction / Q000009:adverse effects*; D011247:Pregnancy; D011379:Prognosis
chemical_list: D006063:Chorionic Gonadotropin; D004958:Estradiol; D008596:Menotropins