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Aromatase Inhibitors

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Infertility in Women with Polycystic Ovary Syndrome

Abstract

Aromatase inhibitors (AIs) were introduced 15 years ago as possible oral agents for ovulation induction in polycystic ovary syndrome (PCOS) patients. Although clomiphene citrate (CC) has been the first line medical treatment for ovulation in PCOS patients for over 60 years, enough evidence has now accumulated to suggest that AIs for ovulation induction should supplant CC. The principle AI studied has been letrozole. Grade 1 evidence in the form of meta-analysis and large randomised double blind controlled studies demonstrate an improvement in percentage of PCOS patients ovulating with letrozole compared to CC, increased pregnancy and live birth rates compared to CC, and fewer side effects. Finally, because of the short half-life of letrozole, especially compared to CC, there is now less concern regarding any adverse effects on foetal development. In conclusion, it now appears that letrozole should be a first line treatment for ovulation induction in infertile patients with PCOS.

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Authors and Affiliations

  1. Division of Reproductive Sciences, University of Toronto, Toronto, ON, M5S 1A1, Canada

    Nivin Samara & Robert F. Casper

  2. Lunenfeld-Tanenbaum Research Institute, Mount Sinai Hospital, Toronto, ON, M5G 1X5, Canada

    Nivin Samara & Robert F. Casper

  3. TRIO Fertility, 655 Bay St, Suite 1101, Toronto, ON, M5G2K4, Canada

    Nivin Samara & Robert F. Casper

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  1. Nivin Samara
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  2. Robert F. Casper
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Correspondence to Robert F. Casper .

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Editors and Affiliations

  1. Unit of Reproductive Medicine and Surgery, ASMN-IRCCS of Reggio Emilia, Reggio Emilia, Italy

    Stefano Palomba

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Samara, N., Casper, R.F. (2018). Aromatase Inhibitors. In: Palomba, S. (eds) Infertility in Women with Polycystic Ovary Syndrome. Springer, Cham. https://doi.org/10.1007/978-3-319-45534-1_10

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  • DOI: https://doi.org/10.1007/978-3-319-45534-1_10

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