Could myo-inositol soft gel capsules outperform clomiphene in inducing ovulation? Results of a pilot study.

OBJECTIVE: Insulin resistance is known to worsen polycystic ovarian syndrome (PCOS). The management of insulin resistance is crucial in the treatment of PCOS and insulin-sensitizing molecule as myo-inositol (MYO) seems to have promising effects. The aim of our pilot study was to study whether supplementation with MYO can improve patients' sensitivity to clomiphene citrate (CC) in terms of ovulation and pregnancy rates.

PATIENTS AND METHODS: This study included 26 patients with PCOS, eligible to ovulation induction with CC. All of them received MYO in combination with CC and folic acid, following the usual protocol. Results concerning ovulation and pregnancy rates were compared to those from our historical cohort of PCOS patients treated with CC alone.

RESULTS: Ovulation rate was significantly higher with MYO+CC than with CC alone (65.5% vs. 42%, p=0.0001). The number of patients sensitive to 50 mg/d was 54% with MYO vs. 40% in our reference cohort (NS). The total resistance rate was 19% vs. 27% in the reference cohort (NS). Cumulative pregnancy rate with MYO+CC was 53.8% vs. 42.2% with CC alone (NS). Pregnancy rates per initiated cycle were 16.1% with MYO vs. 12.6% in the historical cohort (NS).

DISCUSSION: Although the differences were not significant for most outcomes, probably due to the small number of patients, our pilot study seemed to show a benefit of supplementation with MYO during ovulation induction with CC in PCOS patients.

CONCLUSIONS: This study proves the great interest of a RCT and re-opens the possibilities of insulin-sensitizing agents in the treatment of anovulatory patients with PCOS, such as natural products like MYO.