Inositol for Polycystic Ovary Syndrome: A Systematic Review and Meta-analysis to Inform the 2023 Update of the International Evidence-based PCOS Guidelines.
Level 1 - systematic review of randomized trials
Systematic review and meta-analysis of clinical trials
PubMed 38163998 · doi:10.1210/clinem/dgad762
What was done
Systematic review and meta-analysis searching Medline, PsycInfo, EMBASE, All EBM, and CINAHL from inception to August 2022 to evaluate inositol (myo-inositol, D-chiro-inositol [DCI], alone or in combination) for polycystic ovary syndrome (PCOS) to inform the 2023 international guideline update. Outcomes included hormonal, metabolic, lipid, psychological, anthropometric, reproductive measures, and adverse events. The review included 30 trials (n = 2,230; 1,093 intervention, 1,137 control), with 19 trials pooled quantitatively across meta-analyses.
What was found
The abstract reports study and participant counts but provides no numerical effect estimates, confidence intervals, or p-values. Qualitatively, myo-inositol or DCI suggested benefits for some metabolic parameters, and DCI showed potential benefits for ovulation, but inositol had no apparent effect on other outcomes. Metformin appeared more effective than inositol for waist-hip ratio and hirsutism, while reproductive outcomes were similar and BMI findings were very uncertain. Myo-inositol had fewer gastrointestinal adverse events compared with metformin.
Why it matters
Commissioned for the 2023 International Evidence-based PCOS Guidelines, this review clarifies that although inositol is better tolerated than metformin, evidence supporting its clinical efficacy across key PCOS endpoints remains limited and inconclusive.
Limits
The abstract notes substantial uncertainty across multiple endpoints, with only 3 of 13 assessed comparisons eligible for meta-analysis. Specific numerical effect sizes, subgroup analyses by inositol isomer ratio/dosage, trial risk-of-bias details, and long-term clinical endpoints (such as live birth rates) are not reported in the abstract.