Abstract: Objective: The aim of this study is to examine the association between the various risk factors associated with umbilical cord thrombosis, and to evaluate perinatal outcomes. Methods: A retrospective study of umbilical cord thrombi enrolled between 2015~2018 was carried out. Data were analyzed from the medical archives of Tongji Hospital, Huazhong University of Science and Technology. The diagnoses of all cases were confirmed by histopathology. Results:5 of 8 cases were umbilical vein embolism and 3 were umbilical vein thrombi. Gross examination reported 6 cases of additional cord abnormalities, including 2 cases of anomalous of umbilical cord lengths, 2 cases of hyper-coiling, 1 case of swollen cord with deficiency of Wharton’s jelly, and 1 case of placenta velamentous. There are 4 cases termed gestational diabetes disorders, including 3 were gestational diabetes mellitus and one had a history of type I diabetes. Clinical findings depicted that the chief complaint of 4 patients was decreased fetal movement, 3 patients were unsatisfied with electronic fetal monitoring (EFM) and 1 was routine delivery. Perinatal outcomes: With the exception of 2 stillbirths, the remaining 6 cases were terminated by cesarean section. Six infants are alive, including one was SGA（small for gestational age）,one was LBW（low birth weight）and one was VLBW that all infants transferred to neonatology department. Conclusion: We have observed that umbilical structural dysplasia and abnormal blood glucose may lead to the formation of thrombosis. Focus on important signs from prenatal ultrasound, EFM tests and fetal movements can help in improving the screening rate of umbilical cord thrombi. Our results support in the more effective approach of performing emergency cesarean section as soon as possible completed with antenatal corticosteroid therapy for fetal lung maturation in the third trimester.

Key words: thrombosis of umbilical cord, perinatal outcome, risk factors