Abstract: We included five RCTs with 414 participants. The comparisons in the included trials were as follows: CHM versus clomiphene, CHM plus clomiphene versus clomiphene (with or without ethinyloestradiol cyproterone acetate (CEA)), CHM plus follicle aspiration plus ovulation induction versus follicle aspiration plus ovulation induction alone, and CHM plus laparoscopic ovarian drilling (LOD) versus LOD alone. The overall quality of the evidence for most comparisons was very low. None of the included studies reported live birth rate, and only one study reported data on adverse events. When CHM was compared with clomiphene (with or without LOD in both arms), there was no evidence of a difference between the groups in pregnancy rates (odds ratio (OR) 1.98, 95% confidence interval (CI) 0.78 to 5.06; two studies, 90 participants, I² statistic = 0%, very low quality evidence). No study reported data on adverse events. When CHM plus clomiphene was compared with clomiphene (with or without CEA), there was low quality evidence of a higher pregnancy rate in the CHM plus clomiphene group (OR 2.62, 95% CI 1.65 to 4.14; three RCTs, 300 women, I² statistic = 0%,low quality evidence). No data were reported on adverse events. When CHM with follicle aspiration and ovulation induction was compared with follicle aspiration and ovulation induction alone, there was no evidence of a difference between the groups in pregnancy rates (OR 1.60, 95% CI 0.46 to 5.52; one study, 44 women, very low quality evidence), severe luteinized unruptured follicle syndrome (LUFS) (OR 0.60, 95% CI 0.06 to 6.14; one study, 44 women, very low quality evidence), ovarian hyperstimulation syndrome (OHSS) (OR 0.16, 95% CI 0.00 to 8.19; one study, 44 women, very low quality evidence) or multiple pregnancy (OR 0.60, 95% CI 0.06 to 6.14; one study, 44 women, very low quality evidence). When CHM with LOD was compared with LOD alone, there was no evidence of a difference between the groups in rates of pregnancy (OR 3.50, 95% CI 0.72 to 17.09; one study, 30 women, very low quality evidence), No data were reported on adverse events. There was no evidence of a difference between any of the comparison groups for any other outcomes. The quality of the evidence for all other comparisons and outcomes was very low. The main limitations in the evidence were failure to report live birth or adverse events, failure to describe study methods in adequate detail and imprecision due to very low event rates and wide CIs. There is insufficient evidence to support the use of CHM for women with PCOS and subfertility. No data are available on live birth, and there is no consistent evidence to indicate that CHM influences fertility outcomes. However there is very limited low quality evidence to suggest that the addition of CHM to clomiphene may improve pregnancy rates. There is insufficient evidence on adverse effects to indicate whether CHM is safe.

Plain-language summary: We searched evidence from commonly used databases and it is current to 9 June 2016. We included five RCTs with 414 participants. These included studies comparing CHM to western medicine, CHM plus western medicine versus western medicine, and CHM plus surgery versus surgery. All the included studies were in Chinese. All studies had fewer than six menstrual cycles treatment duration and less than one year follow-up duration. None of the included studies reported live birth, all reported pregnancy, two reported ovulation and only one reported adverse events. There was insufficient evidence to support the use of CHM for women with PCOS and subfertility. No data were available on live birth, and there was no consistent evidence to indicate that CHM improves fertility outcomes. When CHM was compared with clomiphene (with or without laparoscopic ovarian drilling (LOD) in both arms), the pregnancy rates were no different between the groups. When CHM with follicle aspiration and ovulation induction was compared with follicle aspiration and ovulation induction alone, pregnancy rates were no different between the groups. When CHM with LOD was compared with LOD alone, the pregnancy rates were no different between the groups. However there was limited low quality evidence to suggest that the addition of CHM to clomiphene may improve pregnancy rates. There was no evidence of a difference between any of the comparison groups for any other outcomes. There was insufficient evidence on adverse effects to indicate whether CHM is safe. The quality of the evidence was low or very low. The main limitations in the evidence were failure to report live birth or adverse events, failure to describe study methods in adequate detail, and imprecision, with very low event rates and wide confidence intervals.