Objective: The authors demonstrate two cases of caudal regression syndrome (CRS), a rare malformative syndrom, seen mainly in cases of maternal diabetes with poor metabolic control. Design: Case report. Setting: Department of Obstetrics and Gynecology, Department of Medicine Regional Hospital Pardubice. Cases: The caudal regression syndrome (CRS) was revealed in two women with praegestational diabetes. The diagnosis was made at 18 and 20 weeks. The characteristic ultrasound findings include abrupt interruption of the spine and abnormal position of the lower limbs. The femur bones are fixed in a „V“ pattern, giving a typical „Buddha’s poise“. A complete examination must be conducted for possible urinary and intestinal malformations. The mechanism leading to malformation is discussed in the article. To prevent pregnancy at the time of bad controlled diabetes is the only way to minimaze the risk of producing a congenitally malformed baby including caudal regression syndrom in the population of diabetic mothers. Family planning and supervision by the specialists is always advisable. Conclusion: Early diagnosis of CRS is possible using vaginal ultrasound. Emphasis is placed on the association of abrupt disruption of dorsal or lumbar spine and abnormal images of the lower limbs fixed in a „V“ formation, which is characteristic sign of CRS.

        Key words: caudal regression syndrome, sacral agenesis, maternal diabetes, contraception in medically compromised women