OBJECTIVE: To evaluate the plasma level of YKL-40 in a Danish polycystic ovary syndrome (PCOS) population and to investigate whether YKL-40 is associated with CVD risk factors such as waist circumference, body mass index (BMI), insulin resistance (IR), fasting glucose, fasting insulin, blood lipids and CRP.

DESIGN: Cross-sectional study.

SETTING: Gynecological clinics at three Danish University Hospitals.

PATIENTS: One hundred seventy-one premenopausal women with PCOS recruited consecutively from April 2010 to February 2012. PCOS was diagnosed according to the Rotterdam criteria.

MAIN OUTCOME MEASURES: Plasma level of YKL-40 in four phenotypes of PCOS defined by BMI and IR.

RESULTS: No statistically significant difference was observed in the plasma level of YKL-40 across the four BMI/IR-phenotypes. Positive associations were observed between YKL-40 and BMI, total and free testosterone, triglycerides, and CRP. Total and free testosterone were independent predictors of YKL-40.

CONCLUSION: YKL-40, the marker of low-grade inflammation is not increased in women with PCOS.