Myo-Inositol Vs D-Chiro-Inositol: preliminary data on the comparison between their effects on ovarian function and metabolic factors in women with PCOS.

Background and Aims: Myo-Inositol and D-Chiro-Inositol have shown the capability to improve the ovarian function and metabolism of PCOS patients. The aim of this work is to compare the effects of Myo-Inositol and D-Chiro-inositol in PCOS. Materials and Methods: We enrolled 50 patients, with homogeneous bio-physical features, affected by PCOS and menstrual irregularities, and randomly divided into two groups: 25 were treated with 4 gr of Myo-Inositol/die orally for 6 months, 25 with 1 gr of D-Chiro-Inositol/die orally for 6 months. We analyzed in both groups pre-treatment and post-treatment BMI, systolic and diastolic blood pressure, Ferriman-Gallwey score, Cremoncini score, serum LH, LH/FSH ratio, total and free testosterone, DHEA-S, Δ-4-androstenedione, SHBG, prolactin, glucose /IRI ratio, HOMA index, resumption of regular menstrual cycles. Results: Both isoforms of Inositol reduced systolic blood pressure, serum LH, circulating androgens, prolactin; increased SHBG, and improved LH /FSH ratio and insulin sensitivity. Treatment with Myo-Inositol, compared to D-Chiro-Inositol, was more effective on LH/FSH ratio; decreased more total testosterone, HOMA index, systolic blood pressure, Δ-4-androstenedione and prolactin and, at the same time, increased more SHBG. In contrast, treatment with D-Chiro-Inositol, compared to Myo-Inositol, reduced more levels of serum LH and free testosterone, and increased more the glucose/IRI ratio. Moreover, D-Chiro-Inositol was more effective in restoring regular menstrual cycles. Conclusions: Both isoforms of Inositol were effective in improving ovarian function and metabolism of patients with PCOS, although Myo-Inositol showed the most marked effect on the metabolic profile, whereas D-Chiro-Inositol reduced more hyperandrogenism.