摘要Background:Diagnosis of polycystic ovary syndrome(PCOS)depends on 2003 Rotterdam Criteria.According to these criteria there are four possible combinations resulting in various phenotypes.We aimed(ⅰ)to confirm that the levels of body mass index(BMI),anti-müllerian hormone(AMH)levels and insulin resistance(IR)are higher in PCOS patients and higher in phenotype-A among PCOS patients,and(ii)to determine cut-off values for the diagnosis of PCOS and phenotype-A.Materials and methods:This study was conducted in an IVF Center,between November 2019 and January 2021.Data of infertile women participating in the study was evaluated retrospectively.Parameters such as menstruation pattern,clinical hyperandrogenism,age,BMI,follicle stimulating hormone(FSH),luteinizing hormone(LH),estradiol,thyroid stimulating hormone(TSH),prolactin,AMH,dehydroepiandrosterone sulphate(DHEA-S),fasting blood glucose,fasting insulin levels,antral follicle counts(AFC)and ovarian volumes were recorded for each patient.Women were grouped as PCOS and non-PCOS,and PCOS group was further divided into 4 sub-groups according to their phenotypes.Data of infertile patients with PCOS patients were compared with infer-tile non-PCOS patients and PCOS phenotypes were compared among each other.Results:Data of 244 infertile patients was included in the study.BMI,AMH,AFC,and HOMA-IR were statistically higher in PCOS patients,compared to non-PCOS patients.We found the AMH level of＞3.105 ng/ml to be having 90.8％sensitivity and 90％specificity to diagnose a patient as PCOS.Among different phenotypes,also BMI,AMH,and insulin resistance index(HOMA-IR)levels were significantly higher in infertile PCOS phenotype-A when compared to other three phenotypes(p:0.003,p:0.000,and p:0.000,respectively).The AMH cut-off value to estimate phenotype-A was found as 6.095 ng/ml with 69.2％sensitivity and 86.7％specificity.We did not found threshold levels of BMI and HOMA-IR with high sensitivity to identify phenotype-A.Conclusion:Properly diagnosing PCOS and determining the phenotype are crucial due to the long-term health conditions.Therefore,we suggest that serum AMH level could be included in PCOS diagnosis criteria,and the value of 3.105 ng/ml would have a 90.8％sensitivity and 90％specificity.Also,to identify phenotype-A,AMH level could be used.Therefore,we speculate that AMH may serve to identify PCOS and PCOS phenotype-A in places where ultrasound imaging is not straightforward to perform or not easily accessible.