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Metformin Therapy for the Management of Infertility in Women with Polycystic Ovary Syndrome (Scientific Impact Paper No. 13)

Published: 23/08/2017

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This is the second edition of this paper, previously published in December 2008 with the same title.


Although many women who have polycystic ovaries do not have polycystic ovary syndrome (PCOS), it is a common endocrine disorder affecting 4–12% of women. 

Metformin inhibits the production of hepatic glucose, decreases lipid synthesis, increases fatty acid oxidation and inhibits gluconeogenesis resulting in a decrease in circulating insulin and glucose. Metformin enhances insulin sensitivity at the cellular level and also appears to have direct effects within the ovary. Therefore, it would seem logical to anticipate that insulin lowering and insulin-sensitising treatments, such as metformin, should improve symptoms and reproductive outcomes for women with PCOS.

The purpose of this Scientific Impact Paper is to clarify some of the advice published about the use of metformin therapy for the management of infertility in women with PCOS, and seek to define its role in improving reproductive outcomes in women with PCOS. 


Declaration of interests (guideline developers)

Dr LC Morley MRCOG, Leeds: None declared.

Dr TMH Tang MRCOG, Belfast: Dr Tang acted in an advisory role for Finox Biotech in 2016.

Professor AH Balen FRCOG, Leeds: Chair of the British Fertility Society, and the World Health Organization (WHO) Expert Working Group on the Management of PCOS. Member of WHO International Committee Monitoring Assisted Reproductive Technologies Clinical Terminology Working Group, and Committee Member of the International Steering Committee of the WHO Global Infertility Guidelines Group.

Professor Balen is a member of the Medical Advisory Board of Infertility Network UK acting as a medical advisor on female infertility. He also provides medical advice to Verity (PCOS national support group); PCOS UK; ALIAS (Androgen Insensitivity Support Group); CAH (Congenital Adrenal Hyperplasia Support Group); and the Turner’s Syndrome Society. He is Patron of Acebabes, the national society for parents and children born by assisted conception.

He has provided ad hoc consultancy services on advisory boards for Astra Zeneca, Clear Blue, Ferring Pharmaceuticals, Glaxo Smith Kline, Gideon Richter, Merck Serono, Merck Sharp & Dohme, OvaScience (former member of Ethics Committee), Pharmasure and Uteron Pharma.

Professor Balen is the current Chair of the NHS England IVF pricing Group and former Chair of the Clinical Board of IVI UK. He is Director of Genesis Healthcare LLP (private IVF unit within Leeds Fertility, Leeds Teaching Hospitals) and Balance Reproductive Health Ltd (private reproductive medicine business).