Efficacy and safety of Chinese patent medicine Xiao Yao San in polycystic ovary syndrome: A systematic review and meta-analysis

Polycystic ovary syndrome (PCOS) is one of the most common endocrine-metabolic disorders in women of reproductive age worldwide. Previous studies using randomized controlled trials (RCTs) have revealed that Xiao Yao San (XYS), a classic Chinese patent medicine formula, can effectively treat PCOS. However, the entire evidence has yet to be systematically summarized.The aim of this systematic review and meta-analysis of clinical trials was to assess the effect of XYS for the treatment of PCOS.7 databases were thoroughly reviewed for RCTs published from inception to July 2022, assessing the effect of XYS in treating PCOS, including Cochrane Library, PubMed, Embase, Wan Fang Database, Chinese Biomedical Database, China National Knowledge Infrastructure, and China Science and Technology Journal Database. Outcome measures included ovulation rate, pregnancy rate, hormonal levels, and glycemic parameters. Either a random-effects model or a fixed-effect models was used to pool data. Pooled effect sizes were reported as odds ratios (ORs) or standardized mean differences (SMDs) with their 95% confidence intervals (CIs).A total of 9 trials including 736 PCOS patients met the selection criteria. Our results indicate that XYS plus conventional medicines for PCOS significantly improved ovulation rate (OR = 2.45, 95% CI = 1.94 to 3.08, P < 0.001) and pregnancy rate (OR = 2.65, 95% CI = 1.87 to 3.75, P < 0.001), meanwhile decreased levels of fasting insulin (FINS) (SMD = - 0.46, 95% CI: 0.65 to - 0.27, P < 0.001) and homeostatic model assessment for insulin resistance (HOMA-IR) (SMD = - 0.65, 95% CI = - 0.93 to - 0.37, P < 0.001). XYS plus conventional medicines for PCOS did not have a significant impact on levels of total testosterone (T), follicle-stimulating hormone (FSH), luteinizing hormone (LH), and fasting plasma glucose (FPG). No serious adverse reactions were observed.XYS combined with conventional medicines can improve ovulation and pregnancy rates, decrease FINS and HOMA-IR in PCOS patients, indicating that XYS treatment may be used as a promising adjuvant therapy to the conventional medicines of PCOS. However, due to significant heterogeneity and methodological shortcomings, these results should be interpreted with great caution. Larger, higher quality RCTs are needed to rigorously assess the effect of XYS as a complementary therapy in managing PCOS.