Ethnicity and the Prevalence of Polycystic Ovary Syndrome: The Eastern Siberia PCOS Epidemiology and Phenotype Study.

Context: Previous studies have shown that the prevalence of polycystic ovary syndrome (PCOS) may vary according to race/ethnicity, although a few studies have assessed women of different ethnicities who live in similar geographic and socioeconomic conditions.

Objective: To determine the prevalence of PCOS in an unselected multiethnic population of premenopausal women.

Design: A multicenter prospective cross-sectional study.