We evaluated the effect of insulin resistance and free androgen index (FAI) in non-PCOS (polycystic ovary syndrome) infertile women following controlled ovarian hyperstimulation. A prospective study was done on 144 infertile non-PCOS women with regular menstrual cycle. At first, insulin resistance (IR), free androgen index (FAI), PCOM (polycystic ovary morphology), AFC (antral follicle count), and AMH (anti-Müllerian hormone) were assessed. The patients underwent assisted reproductive technology (ART), and then preovulatory follicles and oocytes retrieved were recorded. The variables of the study were compared between two groups of patients with ovarian hyperstimulation syndrome (OHSS) (n=66) and non-OHSS patients (n=78). Of the 9 variables: BMI, HOMA-IR, FAI, AFC, AMH, PCOM, and preovulatory follicles were risk factors, while the age and retrieved oocytes were not. The 7 variables that showed significance in the univariate analyses were determined as independent variables included in the multivariable logistic regression analysis, as a result, a total of 5 risk factors, BMI, HOMA-IR, FAI, PCOM, and preovulatory follicles entered the equation. The maximum contribution was HOMA-IR followed by PCOM, FAI, preovulatory follicles and BMI. Patients with OHSS had higher chance to have ovaries with polycystic morphology (74%), about three times more than patients who did not develop OHSS (29%) (p<0.001). The best cut-points for IR, FAI, AFC, AMH, and preovulatry follicles were 2.36, 3.9, 8, 3.3 ng/ml, and 10, respectively. Patients with a higher value of BMI, FAI, HOMA-IR, and preovulatory follicles and the presence of PCOM are more likely to develop OHSS, which are not confined to PCOS patients.