title: The aromatase inhibitor letrozole increases the concentration of intraovarian androgens and improves in vitro fertilization outcome in low responder patients: a pilot study.
abstract: OBJECTIVE
  To evaluate the impact of aromatase inhibitors as adjuvant treatment in IVF cycles on intraovarian androgens and cycle outcome.
  
  
  METHODS
  Observational, pilot study.
  
  
  METHODS
  University-affiliated IVF unit.
  
  
  METHODS
  One hundred forty-seven low responder patients with a previous canceled IVF cycle; 71 patients were treated with letrozole 2.5 mg plus a high-dose FSH/hMG-antagonist regimen, and 76 patients were similarly treated but letrozole was not employed.
  
  
  METHODS
  In vitro fertilization treatment with an antagonist FSH/hMG protocol with or without letrozole was administered during the first 5 days of stimulation; hormones were evaluated in both serum and follicular fluid.
  
  
  METHODS
  Number of oocytes retrieved, fertilization rate, implantation rate, and pregnancy rate; androstenedione, T, E2, and P values in serum and follicular fluid.
  
  
  RESULTS
  Letrozole-treated patients showed significantly higher levels of follicular fluid T and androstenedione (80.3 vs. 43.8 pg/mL and 57.9 vs. 37.4 mg/mL, respectively). Similarly, these patients had a higher number of oocytes retrieved (6.1 vs. 4.3) and a higher implantation rate (25% vs. 9.4%) despite similar doses of FSH/hMG (3,627 vs. 3,804 IU).
  
  
  CONCLUSIONS
  Adding 2.5 mg of letrozole to a high-dose FSH/hMG antagonist protocol increases intraovarian androstenedione and T concentration and improves IVF cycle outcome in poor responder patients.
authors: IVI-Madrid, Rey Juan Carlos University, Madrid, Spain. jgvelasco@ivi.es
authors: Juan A
authors: JA
authors: Garcia-Velasco
authors: Luis
authors: L
authors: Moreno
authors: Alberto
authors: A
authors: Pacheco
authors: Alfredo
authors: A
authors: Guillén
authors: Luis
authors: L
authors: Duque
authors: Antonio
authors: A
authors: Requena
authors: Antonio
authors: A
authors: Pellicer
mesh_terms: D000328:Adult; D000728:Androgens / Q000378:metabolism*; D047072:Aromatase Inhibitors / Q000494:pharmacology* / Q000627:therapeutic use; D016009:Chi-Square Distribution; D005260:Female; D005307:Fertilization in Vitro / Q000379:methods*; D006801:Humans; D000077289:Letrozole; D009570:Nitriles / Q000494:pharmacology* / Q000627:therapeutic use; D010053:Ovary / Q000187:drug effects* / Q000378:metabolism*; D010062:Ovulation Induction / Q000379:methods; D010865:Pilot Projects; D011247:Pregnancy; D011446:Prospective Studies; D014230:Triazoles / Q000494:pharmacology* / Q000627:therapeutic use
chemical_list: D000728:Androgens; D047072:Aromatase Inhibitors; D009570:Nitriles; D014230:Triazoles; D000077289:Letrozole