The use of ultrasound for measuring ovarian volume has attracted increasing interest in recent years, as it appears to be a valuable technique for identifying tumors in certain risk groups for ovarian carcinoma. Although in all studies performed to date a transabdominal scanning technique has been used, endovaginal sonography seems more promising for studying the ovaries. The aim of this study is to make a comparison between transabdominal and endovaginal scanning of the ovaries. The study was performed in 17 women with regular menstruation and 11 postmenopausal women. Although no significant difference in ovarian volume was found in comparison of measurements made using an endovaginal and a transabdominal transducer, a much clearer image of the ovaries was obtained with the endovaginal transducer. This scanning technique also seems to be better accepted by the patients since it does not require that the bladder be full. Advantages and disadvantages are discussed.