The Effects of Salvia miltiorrhiza on Reproduction and Metabolism in Women with Polycystic Ovary Syndrome: A Systematic Review and Meta-Analysis

OBJECTIVE: Polycystic ovary syndrome (PCOS) is the most common endocrine disorder in women of reproductive age. As a traditional medicine, Salvia miltiorrhiza (S. miltiorrhiza) has been widely used in the treatment of many gynecological diseases, but the efficacy of S. miltiorrhiza in women with PCOS has not been assessed. The purpose of this systematic review and meta-analysis was to evaluate the effectiveness and safety of S. miltiorrhiza in women with PCOS. METHODS: We conducted searches in PubMed, Embase, the Cochrane Library, the China National Knowledge Infrastructure, the Wanfang Database, the Chinese Scientific Journal Database, and the Chinese BioMedical database from inception to December 23, 2020, to identify studies that met the inclusion criteria. The quality of the evidence was estimated using the Cochrane Reviewer Handbook 5.0.0, and the meta-analysis was performed using RevMan 5.3.5 software. RESULTS: Six randomized controlled trials (RCTs) involving 390 patients with PCOS were included. The studies suggested that S. miltiorrhiza extract combined with letrozole (LET) was more effective in improving pregnancy rate (RR: 2.60, 95% CI: 1.06 to 6.39, P=0.04) compared to LET alone. S. miltiorrhiza extract was associated with decreased fasting blood glucose (MD: –0.25, 95% CI: –0.37 to –0.13, P < 0.0001), fasting insulin (MD: –1.16, 95% CI: –1.74 to –0.58, P < 0.0001), total cholesterol (TC) (MD: –0.58, 95% CI: –0.72 to –0.43, P < 0.00001), and triglycerides (TG) (MD: –0.31, 95% CI: –0.35 to –0.26, P < 0.00001) compared with placebo, but not with improvements in body mass index or waist-to-hip ratio (MD: –1.41, 95% CI: –4.81 to 2.00, P=0.42; MD: –0.02, 95% CI: –0.05 to 0.01, P=0.16, respectively). There was a significant difference between S. miltiorrhiza extract combined with cyproterone acetate (CPA) and CPA alone in terms of decreasing TC (MD: –0.77, 95% CI: –0.89 to –0.65, P < 0.00001), TG (MD: –0.43, 95% CI: –0.65 to –0.20, P < 0.0001), and low-density lipoprotein cholesterol (MD: –0.49, 95% CI: –0.66 to –0.33, P < 0.00001) and increasing high-density lipoprotein cholesterol (MD: 0.30, 95% CI: 0.20, 0.40, P < 0.00001). In addition, S. miltiorrhiza extract also decreased testosterone, follicle-stimulating hormone, and luteinizing hormone. The studies did not mention any adverse events with S. miltiorrhiza extract. CONCLUSION: The current studies indicate that S. miltiorrhiza has beneficial effects on reproduction and glucose and lipid metabolism in patients with PCOS, and it is generally safe for clinical application. However, more prospective RCTs with large samples, multiple centers, and longer intervention duration are needed in the future to obtain more reliable conclusions.