title: Combined letrozole and clomiphene versus letrozole and clomiphene alone in infertile patients with polycystic ovary syndrome.
abstract: BACKGROUND
  Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of childbearing age (6.8%-18%), is among the most common causes of infertility due to ovulation factors, and accounts for 55%-70% of infertility cases caused by chronic anovulation. In this study, we used a combination of letrozole and clomiphene in patients resistant to both drugs individually, and studied the effects of this combination in ovulation and pregnancy in resistant PCOS patients.
  
  
  METHODS
  The study population included infertile couples diagnosed as PCOS in the wife. The women used clomiphene for at least six cycles in order to ovulate after failure to form the dominant follicle, and were then put on letrozole for four cycles. Patients who were unable to form the dominant follicle were enrolled on letrozole and clomiphene combination therapy.
  
  
  RESULTS
  One hundred enrolled patients underwent 257 cycles of a combination of letrozole and clomiphene, in which 213 were able to form the dominant follicle (82.9%) and 44 were unable to do so (17.1%). The number of mature follicles was 2.3±1.1. The mean endometrial thickness in patients on the day of human chorionic gonadotropin administration was 8.17±1.3 mm. The pregnancy rate was 42%.
  
  
  CONCLUSIONS
  According to the results of this study, it can be proposed that in PCOS patients resistant to clomiphene and letrozole used as single agents, a combination of the two drugs can be administered before using more aggressive treatment that may have severe complications or surgery. This combination may also be used as a first-line therapy to induce ovulation in severe cases of PCOS in order to save time and expense.
authors.affiliation: Department of Gynecology, Reproductive Health Research Center, Urmia University of Medical Sciences, Ajman, United Arab Emirates.
authors.forename: Masomeh
authors.initials: M
authors.lastname: Hajishafiha
authors.affiliation: Urmia University of Medical Sciences, Ajman, United Arab Emirates.
authors.forename: Meisam
authors.initials: M
authors.lastname: Dehghan
authors.affiliation: Department of Gynecology, Reproductive Health Research Center, Urmia University of Medical Sciences, Ajman, United Arab Emirates.
authors.forename: Nazila
authors.initials: N
authors.lastname: Kiarang
authors.affiliation: Department of Gynecology, Reproductive Health Research Center, Urmia University of Medical Sciences, Ajman, United Arab Emirates.
authors.forename: Nahideh
authors.initials: N
authors.lastname: Sadegh-Asadi
authors.affiliation: Gulf Medical University, Ajman, United Arab Emirates.
authors.forename: Seyed Navid
authors.initials: SN
authors.lastname: Shayegh
authors.affiliation: Urmia University of Medical Sciences, Ajman, United Arab Emirates.
authors.forename: Mohammad
authors.initials: M
authors.lastname: Ghasemi-Rad
mesh_terms: D000328:Adult; D047072:Aromatase Inhibitors / Q000008:administration & dosage / Q000627:therapeutic use; D002996:Clomiphene / Q000008:administration & dosage / Q000627:therapeutic use*; D004359:Drug Therapy, Combination; D005260:Female; D005300:Fertility Agents, Female / Q000008:administration & dosage / Q000627:therapeutic use; D006801:Humans; D007247:Infertility, Female / Q000188:drug therapy* / Q000209:etiology; D000077289:Letrozole; D009570:Nitriles / Q000008:administration & dosage / Q000627:therapeutic use*; D006080:Ovarian Follicle / Q000187:drug effects; D010062:Ovulation Induction / Q000379:methods; D011085:Polycystic Ovary Syndrome / Q000150:complications* / Q000188:drug therapy; D011247:Pregnancy; D018873:Pregnancy Rate; D016896:Treatment Outcome; D014230:Triazoles / Q000008:administration & dosage / Q000627:therapeutic use*; D055815:Young Adult
chemical_list: D047072:Aromatase Inhibitors; D005300:Fertility Agents, Female; D009570:Nitriles; D014230:Triazoles; D002996:Clomiphene; D000077289:Letrozole
keywords: clomiphene; combination therapy; infertility; letrozole; polycystic ovary syndrome