Abstract: Objective We collected and analyzed the coagulation test results of hospitalized newborns with blood transfusion to improve the reference values of coagulation indexes and to provide data support for precise treatment of newborns. Methods Data were collected about the coagulation indexes of 5 669 hospitalized newborns from 46 hospitals in China, and the changes of coagulation indexes in newborns with different gestational ages and different days-old were compared. Results (1) The PT value of newborns in different gestational age groups decreased gradually with the increase of days-old. Compared with the same days-old group, the PT value gradually decreased with the increase of gestational age, the PT value of full-term infants being the lowest. The days-old of 0~4 days, 5~6 days and ≥16 days were statistically significant, but no difference was observed among other age groups. (2) The INR values of newborns in different gestational age groups declined with the increase of days-old. Compared with the same days-old groups, the days-old of 0~4 days, 5~6 days, 7~9 days, 11~13 days and ≥16 days were statistically significant. (3) The APTT value was found to fall with the increased newborn days-old in the three groups. Compared with the same days-old groups, the APTT value of full-term neonates was the lowest, while that of <32 weeks neonates was the highest. There was statistical significance in the 0~6 days, 10~12 days and ≥16 days. (4) With the newborn days-old in the three groups increased, the TT value had a downward trend, and there was statistical significance in the group. Compared with the same days-old, there were differences in TT values among the three groups with 1~2 days, 3~4 days and ≥16 days. (5) With the increase of days-old, the FIB value of newborns in each gestational age group fluctuated. FIB at the same days-old increased with the increase of gestational age, and had statistical significance at 1~4 days, 5~6 days, 11~12 days, 13~14 days and ≥16 days. Conclusion The coagulation function related indexes of newborns at different gestational ages and different days-old seem to have remarkable changes, which can guide the clinical diagnosis and treatment of neonatal coagulation disorders and help formulate the reference range of neonatal coagulation indexes based on gestational ages and days.

Key words: Newborn, Coagulation index, Reference range