The results of a survey of the birth prevalence of congenital anomalies among 27,472 consecutive newborn babies at a large maternity hospital in Tokyo are reported. There were 29 cases with trisomy-21; 5 cases with trisomy-13 syndrome; 5 with trisomy-18 syndrome; 2 with cri-du-chat syndrome; and one each with partial monosomy 4p, partial trisomy 5p, partial trisomy 6p, partial trisomy 9p, partial trisomy 9q, partial monosomy 10p, and partial monosomy 13q. Single cases of the following were observed: the Hallermann-Streiff syndrome, the Treacher-Collins syndrome, achondroplasia, arthrogryposis, the Beckwith-Wiedemann syndrome, the asplenia syndrome, the Klippel-Trenaunay-Weber syndrome, the Marfan syndrome, the Carpenter syndrome, the Goldenhar syndrome, and the Pierre Robin syndrome. The results of follow-ups to determine the life-prognosis of each patient with an autosomal aberration are reported.