Umbrella review of 18 meta-analyses: inositol linked to higher ovulation rate in PCOS

An umbrella review published in BMC Women s Health pooled 18 meta-analyses of randomized controlled trials that compared inositol supplementation with placebo in women with polycystic ovarian syndrome (PCOS). The analysis covered 17,614 participants. Compared with placebo, supplementation was associated with a higher ovulation rate (odds ratio 3.00) and a modest increase in clinical pregnancy rate (odds ratio 1.23) biomedcentral.comBMC Women s Healthbiomedcentral.comOpen source ↗.

Search and inclusion criteria

Inositols, including myo-inositol (MI) and D-chiro-inositol (DCI), are increasingly studied as potential treatments for PCOS, but the evidence has been contradictory. The authors searched PubMed, the Cochrane Library, Scopus and Web of Science for relevant studies up to June 2026.

They included meta-analyses of randomized trials in women with PCOS treated with MI or DCI versus placebo. Outcomes were metabolic, endocrine or anthropometric. Studies that used metformin as the control were excluded. A random-effects model was used to estimate pooled odds ratios and mean differences with 95% confidence intervals.

Hormonal, metabolic and body measures

Inositol supplementation was associated with lower total testosterone (mean difference −13.70) and free testosterone (−0.44). It was also associated with lower follicle-stimulating hormone (−0.82), androstenedione (−1.22), prolactin (−1.58) and dehydroepiandrosterone sulfate (−82.89). Estradiol (2.35) and sex hormone-binding globulin (14.35) were higher biomedcentral.comBMC Women s Healthbiomedcentral.comOpen source ↗.

Among metabolic markers, the review reported lower fasting blood sugar (−0.95), fasting insulin (−2.93), insulin resistance (−1.01) and triglycerides (−24.04).

For anthropometric measures, higher doses of MI were associated with a significant reduction in body mass index (−0.40). Combination therapy with MI plus DCI produced a small decrease in waist-to-hip ratio (−0.02).

The authors noted significant heterogeneity for the majority of the outcomes. They concluded that inositol supplementation may be associated with a modest increase in ovulation and pregnancy rates, as well as favorable metabolic and endocrine profiles, in women with PCOS biomedcentral.comBMC Women s Healthbiomedcentral.comOpen source ↗.