The effectiveness of inositol and metformin on infertile polycystic ovary syndrome women with resistant to letrozole.

Purpose: The purpose is a comparison of effectiveness of myo-inositol and metformin in infertile women with polycystic ovary syndrome (PCOS) treated with letrozole.

Methods: This study is a randomized single-blind controlled clinical trial undertaken in 150 infertile PCOS women. For all patients, letrozole is prescribed at a dose of 7.5 mg per day from the third day of menstruation for 5 days. Patients who did not ovulate were included and divided into three pretreatment groups: group I(control group), 200 µg of folic acid (as a placebo); group II, 1500 mg of metformin daily plus 200 µg of folic acid, and group III, inositol 2 g plus 200 µg of folic acid received twice daily for 3 months. In the last cycle, 7.5 mg letrozole was prescribed for the induction of ovulation. Primary outcomes were ovary function and pregnancy.

Results: The ovarian function was not significantly different in those groups, whereas the ovarian function of inositol + folic acid group in normal BMI found significantly higher than other BMI spectra. In addition, the ovarian function is significantly higher in the inositol + folic acid group by increasing the infertility duration. The incidence of pregnancy is lower in letrozole + folic acid + inositol group than the other groups; however, it is not significant.

Conclusion: The addition of inositol and metformin to the treatment of infertile PCOS women with letrozole resistance improves the ovarian function; however, it is not significant. Of note, inositol was more effective than metformin in patients with normal BMI.

Irct Registration Number: IRCT2017070234845N1.