title: Letrozole combined with low dose highly purified HMG for ovulation induction in clomiphene citrate-resistant infertile Chinese women with polycystic ovary syndrome: a prospective study.
abstract: OBJECTIVE
  There are still open questions about ovulation induction in clomiphene citrate-(CC)-resistant infertile women. Especially little is known about efficacy and safety of letrozole (LTZ) combined with low-dose highly purified human menopausal gonadotropin (Hp-HMG) in women with polycystic ovary syndrome (PCOS).
  
  
  METHODS
  Prospective, single-arm single-center trial in 200 infertile PCOS patients refractory for at least three CC-treatment cycles. Women with hyperandrogenism took Diane-35 for at least 3 months. All patients got LTZ on day 3 for 5 d in combination with Hp-HMG, starting with 75 IU from cycle day 7 and maintained for up to 3 d. The maximum dose was 150 IU. Primary end-points were ongoing and clinical pregnancy rate, secondary end-points mono-follicular development, ovulation rate, OHSS, multiple pregnancy and early pregnancy loss. Major safety end-point was the incidence of adverse events.
  
  
  RESULTS
  Within 395 cycles the ongoing pregnancy rate was 28.24%, for cycles 35.23%, for patients 68%. The rate of ovulation per cycle was 97.7%, percentage of mono-follicular development 70.9%. No severe OHSS, multiple pregnancy, local or systemic side effects were seen.
  
  
  CONCLUSIONS
  LTZ combined with low-dose Hp-HMG is an effective and safe choice for reducing hyperstimulation and increasing pregnancy rate in CC-resistant women with PCOS.
authors.affiliation: a Department of Gynecological Endocrinology , Beijing Obstetrics and Gynecology Hospital, Capital Medical University , Beijing , PR China and.
authors.forename: Yue
authors.initials: Y
authors.lastname: Zhao
authors.affiliation: a Department of Gynecological Endocrinology , Beijing Obstetrics and Gynecology Hospital, Capital Medical University , Beijing , PR China and.|b Department of Women's Health , University Hospital and Faculty of Medicine of the Eberhard Karls University Tuebingen , Tuebingen , Germany.
authors.forename: Xiangyan
authors.initials: X
authors.lastname: Ruan
authors.affiliation: a Department of Gynecological Endocrinology , Beijing Obstetrics and Gynecology Hospital, Capital Medical University , Beijing , PR China and.|b Department of Women's Health , University Hospital and Faculty of Medicine of the Eberhard Karls University Tuebingen , Tuebingen , Germany.
authors.forename: Alfred O
authors.initials: AO
authors.lastname: Mueck
mesh_terms: D000328:Adult; D047072:Aromatase Inhibitors / Q000008:administration & dosage*; D002996:Clomiphene; D005260:Female; D005300:Fertility Agents, Female / Q000008:administration & dosage*; D006801:Humans; D000077289:Letrozole; D008596:Menotropins / Q000008:administration & dosage*; D009570:Nitriles / Q000008:administration & dosage*; D010062:Ovulation Induction / Q000379:methods*; D011247:Pregnancy; D018873:Pregnancy Rate; D011446:Prospective Studies; D014230:Triazoles / Q000008:administration & dosage*
chemical_list: D047072:Aromatase Inhibitors; D005300:Fertility Agents, Female; D009570:Nitriles; D014230:Triazoles; D002996:Clomiphene; D008596:Menotropins; D000077289:Letrozole
keywords: Clomiphene citrate resistance; highly purified human menopausal gonadotropin; letrozole; ongoing pregnancy rate; polycystic ovary syndrome