Supplementary appendix III: Characteristics of studies included in the systematic reviews

Abbreviations: TDS, three times a day; BD, twice daily; CC, clomiphene citrate; OR, ovulation rate; PR, pregnancy rate; AE, adverse events; LBR, low birth rate; MCR, miscarriage rate; MPR, multiple pregnancy rate.

Tang 2010

Metformin versus placebo or no treatment

Study / Population group / Intervention dose / Comparison / Outcomes
Baillargeon 2004 / PCOS / 850mg BD / placebo / OR
Fleming 2002 / PCOS / 850mg BD / placebo / PR, OR, AE
Hoeger 2004a&b / PCOS / 850mg BD / placebo / OR
Jakubowicz 2001 / CC-sensitive PCOS / 500mg TDS / placebo / OR
Karimzadeh 2007 / PCOS / 500mg TDS / placebo / PR
Lord 2006 / PCOS / 500mg TDS / placebo / PR, OR
Moghetti 2000 / PCOS / 500mg TDS / placebo / AE
Nestler 1998 / PCOS / 500mg TDS / placebo / OR
Ng 2001 / CC-resistant PCOS / 500mg TDS / placebo / LBR, PR, OR, AE
Onalan 2005a&b / PCOS / 850mg BD / placebo / OR
Sturrock 2002 / CC-resistant PCOS / 500mg TDS / placebo / OR
Tang 2006 / PCOS / 850mg BD / placebo / PR
Trolle 2007 / PCOS / 850mg BD / placebo / AE
Vandermolen 2001 / CC-resistant PCOS / 500mg TDS / placebo / OR
Yarali 2002 / CC-resistant PCOS / 850mg BD / placebo / LBR, PR, OR, AE

Metformin versus clomiphene citrate

Study / Population group / Intervention / Comparison / Outcomes
Legro 2007 / PCOS / 2X500mg BD / placebo + 150mg clomiphene citrate / LBR, PR, OR, MR, MPR
Palomba 2005 / PCOS / 850mg BD + placebo / placebo + 150mg clomiphene citrate / LBR, PR, OR, MR, MPR
Zain 2008 / PCOS / 1500mg per day / 200mg clomiphene citrate / LBR, PR, OR, MR, MPR

Metformin + clomiphene citrate versus clomiphene citrate

Study / Population group / Intervention / Comparison / Outcomes
El-Biely 2001 / PCOS / 500mg TDS + 150mg clomiphene citrate / no treatment + 150mg clomiphene citrate / PR, OR
Hwu 2005 / CC-resistant PCOS / 500mg TDS + 150mg clomiphene citrate / no treatment + 150mg clomiphene citrate / PR, OR, MR
Jakubowicz 2001 / CC-sensitive PCOS / 500mg TDS + 150mg clomiphene citrate / placebo + 150mg clomiphene citrate / OR
Legro 2007 / PCOS / 2X500mg BD + 150mg clomiphene citrate / placebo + 150mg clomiphene citrate / LBR, PR, OR, MR, MPR
Malkawi 2002 / CC-resistant PCOS / 850mg BD + 200mg clomiphene citrate / placebo + 200mg clomiphene citrate / PR, OR
Moll 2006 / PCOS / 2000mg per day + 150mg clomiphene citrate / placebo + 150mg clomiphene citrate / LBR, PR, OR
Nestler 1998 / PCOS / 500mg TDS + 50mg clomiphene citrate / placebo + 50mg clomiphene citrate / OR
Ng 2001 / CC-resistant PCOS / 500mg TDS + 100mg clomiphene citrate / placebo + 100mg clomiphene citrate / OR
Sturrock 2002 / CC-resistant PCOS / 500mg TDS / placebo + 100mg clomiphene citrate / OR
Vandermolen 2001 / CC-resistant PCOS / 500mg TDS + 150mg clomiphene citrate / Placebo + 150mg clomiphene citrate / LBR, PR, OR, MR, MPR
Zain 2008 / PCOS / 1500mg per day + 200mg clomiphene citrate / 200mg clomiphene citrate / LBR, PR, OR, MR, MPR

Palomba 2009

Metformin + clomiphene citrate versus metformin

Study / Population group / Intervention / Comparison / Outcomes
Legro 2007 / PCOS / 2000mg per day + 150mg clomiphene citrate / 2000mg per day / LBR, PR, OR, MR, AE
Zain 2008 / PCOS / 1500mg per day + 200mg clomiphene citrate / 1500mg per day / LBR, PR, OR, MR, AE

Moll 2007

Metformin versus placebo

Study / Population group / Intervention dose / Comparison / Outcomes
Fleming 2002 / PCOS / 850mg BD / placebo / PR
Ng 2001 / CC-resistant PCOS / 500mg TDS / placebo / LBR, PR
Tang 2006 / PCOS / 850mg BD / placebo / PR

Metformin versus clomiphene citrate

Study / Population group / Intervention / Comparison / Outcomes
Legro 2007 / PCOS / 2X500mg BD / placebo + 150mg clomiphene citrate / LBR, PR
Palomba 2005 / PCOS / 850mg BD + placebo / placebo + 150mg clomiphene citrate / LBR, PR

Metformin + clomiphene citrate versus clomiphene citrate

Study / Population group / Intervention / Comparison / Outcomes
El-Biely 2001 / PCOS / 500mg TDS + 150mg clomiphene citrate / no treatment + 150mg clomiphene citrate / PR, OR
Hwu 2005 / CC-resistant PCOS / 500mg TDS + 150mg clomiphene citrate / no treatment + 150mg clomiphene citrate / PR, OR, MR
Khorram 2006* / CC-naïve PCOS / 500mg TDS + 100mg clomiphene citrate / no treatment + 100mg clomiphene citrate / LBR, PR
Kocak 2002* / CC-resistant PCOS / 850mg BD + 100mg clomiphene citrate / placebo + 100mg clomiphene citrate / LBR, PR
Legro 2007 / PCOS / 2X500mg BD + 150mg clomiphene citrate / placebo + 150mg clomiphene citrate / LBR, PR, OR, MR, MPR
Malkawi 2002 / CC-resistant PCOS / 850mg BD + 200mg clomiphene citrate / placebo + 200mg clomiphene citrate / PR, OR
Moll 2006 / PCOS / 2000mg per day + 150mg clomiphene citrate / placebo + 150mg clomiphene citrate / LBR, PR, OR
Raja 2005* / CC-naïve PCOS / 500mg TDS + 50mg clomiphene citrate / no treatment + 50mg clomiphene citrate / LBR, PR
Sahin 2004* / CC-naïve PCOS / 850mg BD + 100mg clomiphene citrate / no treatment + 100mg clomiphene citrate / LBR, PR
Singh 2001* / CC-naïve PCOS / 500mg BD + 50mg clomiphene citrate / no treatment + 50mg clomiphene citrate / LBR, PR
Sturrock 2002 / CC-resistant PCOS / 500mg TDS / placebo + 100mg clomiphene citrate / OR
Vandermolen 2001 / CC-resistant PCOS / 500mg TDS + 150mg clomiphene citrate / Placebo + 150mg clomiphene citrate / LBR, PR, OR, MR, MPR

*Inadequate randomization or randomization method is unclear

Creanga2008

Metformin versus placebo

Study / Population group / Intervention dose / Comparison / Outcomes
Baillargeon 2004 / PCOS / 850mg BD / placebo / OR
Fleming 2002 / PCOS / 850mg BD / placebo / OR
Hoeger 2004 / PCOS / 850mg BD / placebo / OR
Kocak 2002* / CC-resistant PCOS / 850mg BD / placebo / OR
Nestler 1996* / PCOS / 500mg TDS / placebo / OR
Nestler 1998 / PCOS / 500mg TDS / placebo / OR
Ng 2001 / CC-resistant PCOS / 500mg TDS / placebo / OR
Onalan 2005 / PCOS / 850mg BD / placebo / OR
Sahin 2004* / CC-naïve PCOS / 850mg BD / placebo / OR
Vandermolen 2001 / CC-resistant PCOS / 500mg TDS / placebo / OR
Yarali 2002 / CC-resistant PCOS / 850mg BD / placebo / OR

Metformin + clomiphene citrate versus clomiphene citrate

Study / Population group / Intervention / Comparison / Outcomes
El-Biely 2001 / PCOS / 500mg TDS + 150mg clomiphene citrate / no treatment + 150mg clomiphene citrate / OR
Hwu 2005 / CC-resistant PCOS / 500mg TDS + 150mg clomiphene citrate / no treatment + 150mg clomiphene citrate / OR
Khorram 2006* / CC-naïve PCOS / 500mg TDS + 100mg clomiphene citrate / no treatment + 100mg clomiphene citrate / OR
Kocak 2002* / CC-resistant PCOS / 850mg BD + 100mg clomiphene citrate / placebo + 100mg clomiphene citrate / OR
Legro 2007 / PCOS / 2X500mg BD + 150mg clomiphene citrate / placebo + 150mg clomiphene citrate / OR
Malkawi 2002 / CC-resistant PCOS / 850mg BD + 200mg clomiphene citrate / placebo + 200mg clomiphene citrate / OR
Moll 2006 / PCOS / 2000mg per day + 150mg clomiphene citrate / placebo + 150mg clomiphene citrate / OR
Nestler 1998 / PCOS / 500mg TDS + 50mg clomiphene citrate / placebo + 50mg clomiphene citrate / OR
Ng 2001 / CC-resistant PCOS / 500mg TDS + 100mg clomiphene citrate / placebo + 100mg clomiphene citrate / OR
Refaie 2005* / CC-naïve PCOS / 500mg TDS + ?mg clomiphene citrate / no treatment + ?mg clomiphene citrate / OR
Vandermolen 2001 / CC-resistant PCOS / 500mg TDS + 150mg clomiphene citrate / Placebo + 150mg clomiphene citrate / OR

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