Background/aim: Polycystic ovarian syndrome (PCOS) is one of the most common causes of infertility. One of the best therapeutic options for PCOS patients is intracytoplasmic sperm injection (ICSI). In vitro maturation (IVM) can also be a useful technique for these women. The goal of this study was to evaluate both the zona pellucida (ZP) birefringence and meiotic spindle (MS) of in vivo- and in vitro-matured oocytes from PCOS patients using the PolScope system. Materials and methods: Immature oocytes undergoing IVM and MII oocytes were obtained from PCOS patients in an ICSI program. Using PolScope, the presence of MS and ZP birefringence was assessed in both in vivo-matured oocytes (n = 32) and IVM oocytes (n = 24). Oocytes were classified as having highly birefringent (HB) ZP and lowly birefringent (LB) ZP. Furthermore, the rates of fertilization after ICSI were evaluated. Results: The maturation rate was 68.5% after IVM. The percentage of a HB-ZP was significantly higher in the IVM oocytes than in vivo-matured ones (58.3% vs. 31.2%, respectively; P = 0.04). There were similar outcomes for the fertilization rates and MS detection between the two groups (P = 0.80 and P = 0.53, respectively). Conclusion: Clinical IVM is a safe technology for the maturation and maintenance of oocyte integrity in PCOS patients. The use of the noninvasive PolScope is recommended for detection of healthy oocytes in ICSI.