Objective. To assess the quality of oocytes, embryos, and outcomes of in vitro fertilization (IVF) cycles in patients with diminished ovarian reserve (OR) who received inositol before infertility treatment. Subjects and methods. An observational comparative multicenter study pre-IVF TIDOR included 270patients. Group 1 (n=158) took inositol 4000 mg + folic acid 400цg (Inofert, Italfarmaco S.p.A., Italy); Group 2 (n=112) did not receive inositol before infertility treatment using IVF. The inclusion criteria were age <38years; a history of ovarian surgery; AMH <1.0 pg/ml, transfer of 42 embryos (ET) in the ovarian stimulation (OS) cycle. Results. In Group 1 and Group 2, mature oocytes (n=5 (0-7) and 2 (0- 5); p = 0.049) and good- quality embryos (42.2 and 30.1%; p = 0.049) were retrieved; there was a high rate of ET-induced pregnancy (38.1and 30.0%; p = 0.041). Conclusion. It is expedient to use inositol (Inofert, Italfarmaco S.p.A., Italy) in women younger than 38years after ovarian surgery in order to enhance