Effects of d-chiro-inositol in lean women with the polycystic ovary syndrome

Endocr Pract. 2002 Nov-Dec;8(6):417-23. doi: 10.4158/EP.8.6.417.


Objective: To determine whether the administration of D-chiro-inositol, a putative insulin-sensitizing drug, would affect the concentration of circulating insulin, the levels of serum androgens, and the frequency of ovulation in lean women with the polycystic ovary syndrome.

Methods: In 20 lean women (body mass index, 20.0 to 24.4 kg/m 2) who had the polycystic ovary syndrome, treatment was initiated with either 600 mg of D-chiro-inositol or placebo orally once daily for 6 to 8 weeks. We performed oral glucose tolerance tests and measured serum sex steroids before and after therapy. To monitor for ovulation, we determined serum progesterone concentrations weekly.

Results: In the 10 women given D-chiro-inositol, the mean (+/- standard error) area under the plasma insulin curve after oral administration of glucose decreased significantly from 8,343 +/- 1,149 mU/mL per min to 5,335 +/- 1,792 mU/mL per min in comparison with no significant change in the placebo group (P = 0.03 for difference between groups). Concomitantly, the serum free testosterone concentration decreased by 73% from 0.83 +/- 0.11 ng/dL to 0.22 +/- 0.03 ng/dL, a significant change in comparison with essentially no change in the placebo group (P = 0.01). Six of the 10 women (60%) in the D-chiro-inositol group ovulated in comparison with 2 of the 10 women (20%) in the placebo group (P = 0.17). Systolic (P = 0.002) and diastolic (P = 0.001) blood pressures, as well as plasma triglyceride concentrations (P = 0.001), decreased significantly in the D-chiro-inositol group in comparison with the placebo group, in which these variables either increased (blood pressure) or decreased minimally (triglycerides).

Conclusion: We conclude that, in lean women with the polycystic ovary syndrome, D-chiro-inositol reduces circulating insulin, decreases serum androgens, and ameliorates some of the metabolic abnormalities (increased blood pressure and hypertriglyceridemia) of syndrome X.

Publication types

  • Clinical Trial
  • Randomized Controlled Trial
  • Research Support, Non-U.S. Gov't
  • Research Support, U.S. Gov't, P.H.S.

MeSH terms

  • Adolescent
  • Adult
  • Blood Glucose / analysis
  • Blood Pressure
  • Body Mass Index*
  • Double-Blind Method
  • Female
  • Glucose Tolerance Test
  • Humans
  • Inositol Phosphates / therapeutic use*
  • Insulin / blood
  • Insulin Antagonists / therapeutic use*
  • Placebos
  • Polycystic Ovary Syndrome / drug therapy*
  • Polycystic Ovary Syndrome / physiopathology
  • Polysaccharides / therapeutic use*
  • Testosterone / blood
  • Triglycerides / blood


  • Blood Glucose
  • Inositol Phosphates
  • Insulin
  • Insulin Antagonists
  • Placebos
  • Polysaccharides
  • Triglycerides
  • inositol phosphate glycan
  • Testosterone