The purpose of this study was to investigate the potential value of three‐dimensional ultrasound for the assessment of normal uterine anatomy and the diagnosis of congenital uterine anomalies. A total of 61 patients with a history of recurrent miscarriage or infertility and who had previously been investigated by hysterosalpingography were recruited into the study. They first underwent a conventional two‐dimensional transvaginal ultrasound scan. At the end of the examination, three‐dimensional ultrasound volumes were recorded and stored in the machine computer memory. The examination of planar reformatted sections was than used for the assessment of uterine morphology and the diagnosis of congenital anomalies. On three‐dimensional scanning, the most useful plane was a transverse section through the whole length of the uterus from the fundus to the cervix. Hysterosalpingography showed a normal uterus in 44 (72.1%) patients, an arcuate uterus in nine (14.8%) and a major fusion defect in three cases (4.9%). Five patients (8.2%) had large fibroids which were distorting the uterine cavity. Good‐quality two‐dimensional ultrasound images were obtained in 60 (98.3%) and three‐dimensional images in 58 (95.1%) cases. All poor images were caused by large uterine fibroids. Comparison between hysterosalpingography and ultrasound showed that five false‐positive diagnoses of arcuate uterus and three of major uterine anomalies were made on two‐dimensional scans. Three‐dimensional ultrasound agreed with hysterosalpingography in all cases of arcuate uterus and major congenital anomalies. The ability to visualize both the uterine cavity and the myometrium on a three‐dimensional scan facilitated the diagnosis of uterine anomalies and enabled easy differentiation between subseptate and bicornuate uteri. Copyright © 1995 International Society of Ultrasound in Obstetrics and Gynecology