title: A comparison of the efficacy of two doses of letrozole alone or with continuous recombinant follicle-stimulating hormone for ovulation induction in anovulatory women.
abstract: OBJECTIVE
  To determine the efficacy of letrozole alone or with recombinant follicle-stimulating hormone (rFSH) for ovarian induction in anovulatory women.
  
  
  METHODS
  A total of 322 patients undergoing intrauterine insemination (IUI) were included in this retrospective study. Letrozole (2.5 or 5.0 mg) was administered from days 5 to 9 of menses, alone or followed with rFSH started on day 9 until the day of human chorionic gonadotropin administration. A single IUI was performed 24 h after ovulation.
  
  
  RESULTS
  The number of follicles, endometrial thickness and serum estradiol levels were significantly higher in the letrozole + rFSH groups than in the letrozole-alone groups (p < 0.05), but no significant difference was found between the two doses of letrozole, whether alone or with rFSH. Women treated with 5.0 mg/day of letrozole + rFSH required a total dose of rFSH similar to women treated with 2.5 mg/day of letrozole + rFSH (230.77 ± 118.29 vs. 258.55 ± 130.13 IU, respectively; p = 0.205). There was no significant difference in pregnancy rates between the two doses of letrozole, whether alone or with rFSH.
  
  
  CONCLUSIONS
  Treatment with letrozole + rFSH was more efficacious than letrozole alone for pregnancy in the IUI program; however, the effect of 5.0 mg/day of letrozole versus 2.5 mg/day of letrozole on ovulation was equivalent, regardless of whether rFSH was used.
authors.affiliation: Department of Reproductive Medicine, First Affiliated Hospital, College of Medicine, Xi'an Jiaotong University, Xi'an, People's Republic of China.
authors.forename: Hai-Yan
authors.initials: HY
authors.lastname: Wang
authors.forename: Peng-Sheng
authors.initials: PS
authors.lastname: Zheng
mesh_terms: D000328:Adult; D000858:Anovulation / Q000188:drug therapy*; D047072:Aromatase Inhibitors / Q000008:administration & dosage / Q000494:pharmacology*; D004359:Drug Therapy, Combination; D005260:Female; D005640:Follicle Stimulating Hormone / Q000008:administration & dosage / Q000494:pharmacology*; D006801:Humans; D007315:Insemination, Artificial / Q000379:methods*; D000077289:Letrozole; D009570:Nitriles / Q000008:administration & dosage / Q000494:pharmacology*; D010062:Ovulation Induction / Q000379:methods*; D016896:Treatment Outcome; D014230:Triazoles / Q000008:administration & dosage / Q000494:pharmacology*
chemical_list: D047072:Aromatase Inhibitors; D009570:Nitriles; D014230:Triazoles; D000077289:Letrozole; D005640:Follicle Stimulating Hormone