Congenital uterine malformations are genital tract anomalies that can arise at different stages in the development of the Müllerian ducts. Their exact epidemiology is unclear. Depending on the type of uterine anomaly, they can be asymptomatic or imply adverse reproductive outcomes (infertility, recurrent miscarriages, preterm labor), thus altering the quality of life. The American Society of Reproductive Medicine (ASRM) most common classification system divides uterine malformations into seven categories. The CONUTA (Congenital Uterine Anomalies) working group set up by the European Society of Human Reproduction and Embryology (ESHRE) together with the European Society for Gynecological Endoscopy (ESGE) developed and published in 2013 the new classification system of congenital uterine malformations which are grouped by classes according to common impairment of the primary embryological process, respectively formation, fusion, resorption. To plan their therapeutic management, one must first determine the exact type of uterine anomaly. Several methods can be used for diagnosing uterine anomalies. Three-dimensional ultrasound (3D-US) represents the essential diagnostic tool and should be used as the first line in most cases where the uterine malformation is suspected.