The 40:1 inositol ratio restored ovulation best in PCOS/PMOS

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Nutrients and supplements Clinical trial · 2019

Key finding

Women with PCOS took one of seven inositol formulations (2 g twice daily for three months): D-chiro-inositol alone, or myo-inositol and D-chiro-inositol in ratios from 1:3.5 to 80:1. The 40:1 ratio, the balance found naturally in the body, was the most effective at restoring ovulation and improving hormone and insulin measures. Formulations with more D-chiro-inositol worked less well. The study was small (56 women, 8 per group), and it confirmed earlier laboratory findings.

What it means for practice

When recommending inositol for women with PCOS/PMOS, choose a product that provides myo-inositol and D-chiro-inositol in the 40:1 ratio, and review cycles and ovulation after about three months.

Reference

Nordio M, Basciani S, Camajani E. The 40:1 myo-inositol/D-chiro-inositol plasma ratio is able to restore ovulation in PCOS patients: comparison with other ratios. Eur Rev Med Pharmacol Sci 2019;23(12):5512-5521.

Read the original paper

Summarised by the Draxer Clinical Advisory Department for health professionals. It supports, and does not replace, clinical judgement.

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