Abstract: Objective To explore the blood routine index reference value of hospitalized newborns with blood transfusion throughout the country and to provide data support for blood routine reference range of newborns in different gestational ages. Methods The basic information of 5 669 hospitalized newborns with blood transfusion were collected and divided into three groups according to their gestational age：<32 w group,32~36 w group and ≥ 37 w group. The data of blood routine indexes of newborns in different gestational ages before blood transfusion were collected and analyzed. Results The erythrocyte count,the hematocrit and the hemoglobin of newborns in different gestational age groups decreased with the increase of postnatal days. There were statistical differences in the erythrocyte count of newborns on the day 0,1~2,6~7 and 9~10,but there were no differences among other time groups. The hematocrit and the hemoglobin of newborns in different gestational age groups decreased with the increase of postnatal days. There were statistical differences in hematocrit and hemoglobin among groups on the day 0~1, 1~2 and 3~4, but there were no differences among other groups. The white blood cell count of newborns in different gestational age groups decreased with the increase of postal days, and there were statistical differences among groups on day 0~1, 1~2, 2~3, 3~4, 6~7, 8~9 and ≥16 d, but no differences among other groups. The platelet count of newborns in different gestational age groups increased obviously from day 0~1 to ≥16 after birth. There were statistical differences in platelet count among groups on day 0~1, 1~2 , 7~9, 11~14 and ≥16 after birth,but there were no differences among other groups. Conclusion The changes of blood routine indexes in newborns with blood transfusion are significant,and it is helpful to guide clinical diagnosis and precise treatment to formulate the reference range of blood routine according to gestational age and postnatal days.

Key words: Newborn, Blood routine, Reference range