Key finding
This review brought together 13 meta-analyses of randomised trials. Compared with placebo or folic acid alone, inositol more than doubled the chance of ovulation (RR 2.75, 95% CI 1.71 to 4.41) and of live birth (RR 2.29, 95% CI 1.07 to 4.93). It also lowered testosterone, LH, fasting insulin and insulin resistance (HOMA-IR), and raised SHBG, the protein that binds testosterone. Compared with metformin, most results were similar, but pregnancy rates were higher with inositol (RR 1.43, 95% CI 1.14 to 1.79).
Inositol is a reasonable option for women with PCOS/PMOS who want to improve ovulation or insulin resistance, including those who don't tolerate metformin. Myo-inositol, alone or with folic acid, did better than D-chiro-inositol on its own. Most of the evidence was rated low or moderate quality, so it should sit alongside lifestyle advice and standard care rather than replace them.
Duan M, Yang M, Li C, Wu X, Yin X, Zhu H. Effects of inositol in women with polycystic ovary syndrome: an umbrella review of meta-analyses from randomized controlled trials. Front Endocrinol (Lausanne). 2026;17:1741509.
Read the original paperSummarised by the Draxer Clinical Advisory Department for health professionals. It supports, and does not replace, clinical judgement.