Journal of Assisted Reproduction and Genetics

, Volume 26, Issue 1, pp 19–24 | Cite as

Comparison of letrozole with continuous gonadotropins and clomiphene-gonadotropin combination for ovulation induction in 1387 PCOS women after clomiphene citrate failure: a randomized prospective clinical trial

  • Ashalatha Ganesh
  • Sourendra Kant Goswami
  • Ratna Chattopadhyay
  • Koel Chaudhury
  • Baidyanath Chakravarty



Letrozole, though reported to be an effective ovulation inducing agent, warrants larger randomized trials. The purpose of this study is to compare the efficacy of letrozole with that of rFSH and clomiphene citrate(CC)/rFSH for ovarian stimulation in IUI cycles.


Randomized, prospective, single-blinded clinical trial. 1387 PCOS women after CC failure were randomized into three groups: Group A received letrozole, Group B received CC with two doses rFSH and Group C received continuous rFSH day 2 onwards until hCG injection.


Group A, B and C had an ovulation rate of 79.30%, 56.95% and 89.89% and cycle cancellation rate of 20.70%, 43.05% and 10.11%, respectively. Pregnancy rates in Group A, B and C were 23.39%, 14.35% and 17.92%, while the miscarriage rates were 13.80%, 16.67% and 14.52%, respectively.


Letrozole appears to be a suitable ovulation inducing agent in PCOS women with CC failure and is found to be most effective when baseline estradiol level >60 pg/ml.


Baseline estradiol Clomiphene citrate failure Letrozole Ovulation induction rFSH 



One of the authors, Dr. Ashalatha Ganesh sincerely acknowledges the Council of Scientific and Industrial Research (CSIR) for providing financial support. All authors thank Dr Himadri S. Sarkar, PhD., Institute of Reproductive Medicine, Salt Lake, Kolkata, India for measuring various hormone levels in the laboratory. Mr. Soumen Das, a graduate student, is acknowledged for helping with the statistical analysis.


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Copyright information

© Springer Science+Business Media, LLC 2008

Authors and Affiliations

  • Ashalatha Ganesh
    • 1
  • Sourendra Kant Goswami
    • 2
  • Ratna Chattopadhyay
    • 2
  • Koel Chaudhury
    • 1
  • Baidyanath Chakravarty
    • 2
  1. 1.School of Medical Science and TechnologyIndian Institute of TechnologyKharagpurIndia
  2. 2.Institute of Reproductive MedicineKolkataIndia

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