Polycystic ovary syndrome (PCOS) affects 4–20% of reproductive aged women. In the literature, it has been shown that PCOS can be associated with insulin resistance (IR) and metabolic syndrome (MS). The aim of the study was to identify which factors (hormonal, metabolic, clinical or sonographic) were associated with MS and IR in women with PCOS. We conducted a retrospective cohort study of 1,040 women with PCOS, aged from18 to 43 years, who consulted at the Lille University Hospital between 2008 and 2020. The examinations performed included: clinical characteristics, hormonal assessment of ovarian reserve and antral follicular count by vaginal ultrasound, androgen assay, glucose tolerance parameters and lipids. The evaluation of IR was performed according to HOMA (IR if HOMA ≥ 2). When BMI increased within one category, the risk of developing MS raised (OR: 2.80; 95% CI: 2.013–3.918). The presence of IR also increased the risk of developing MS (OR: 3.99; 95% CI: 2.757–5.802). Conversely, SHBG was negatively associated with MS. When the BMI category increased, the risk of developing IR increased (OR: 2.90; 95% CI: 2.12–3.96). The risk of developing IR increased with increasing testosterone (OR: 4.399; 95% CI: 2.68–7.22). Conversely as SHBG and androstenedione decreased, the risk of having an IR was higher. There was no significant association between the occurrence of MS and intrinsic PCOS factors indicating ovarian dysfunction. This study has shown that only clinical characteristics (age, BMI) and metabolic parameters as IR were associated with PCOS. Among biological parameters only SHBG were associated. The link between MS and PCOS is therefore probably not related to ovarian factors, but rather to metabolic parameters. The association between IR and ovarian parameters as testosterone and androstenedione, confirms the close link between insulin and ovarian function.