ObjectivesThe aim of this study was to determine the relationship of ovarian volume (OV) to age, height, and weight in Korean young women with the polycystic ovary syndrome (PCOS) undergoing ultrasonography (US) and to investigate the relationship between ovarian follicle count and volume on US and serum hormone levels including the levels of the anti-Müllerian hormone (AMH) and gonadotropin.MethodsA total of 272 Korean nulliparous women aged 15 to 39 years who were newly diagnosed with PCOS at a university hospital were included in this study. Evaluation of the ovaries and measurement of OVs in all cases were randomly performed by ultrasound. The OV and follicle number (FN) were obtained in all cases.ResultsIn Korean women with PCOS, mean OV was 7.9 ± 3.6 cm3 (right) and 6.7 ± 3.1 cm3 (left). Mean FN in the PCOS group was 14.2 ± 4.6 (right) and 13.8 ± 4.3 (left). OV and ovarian FN were unrelated to patient weight, height and body mass index. The left ovarian FN was related to patient age. AMH levels ranged from 5.31 to 43.1 ng/mL and the mean level was 13.9 ± 7.2 ng/mL. Serum AMH was related to OV and FN, and serum total testosterone was related to FN in Korean women with PCOS.ConclusionsIn Korean nulliparous women with PCOS, OV was smaller than that in other ethnic groups and the right OV was larger than the left OV. Ovarian FN, AMH, testosterone are good markers for the diagnosis of PCOS in Korean women.