This study was aimed to explore the correlation of hemogram changes during pregnancy of healthy women with postpartum blood transfusion. The outpatient and inpatient information of expectant lying-in women in our hospitals was collected, the route blood test, lever and kidney function and blood coagulation function tests were performed from the 4th to the 10th month of pregnancy. The pregnant women without underlying diseases and non-elderly pregnant women with single fetus were selected as the subjects of study. They were divided into postpartum blood transfusion group and non-blood transfusion group. The white blood cell (WBC) count, hemoglobin (Hb) level, platelet (Plt) count, plateletocrit (PCT), mean platelet volume (MPV), platelet distribution width (PDW) were compared in 2 groups. The results showed that 68 cases out of 450 expectant lying-in women received blood transfusion, among them 30 cases with complete data of puerperal transfusion were taken as blood transfusion group, the 28 cases of non transfusion puerperal as control group. There was no significant difference of hemogram changes between the two groups. However, there was a slight decline in Plt count and Hb level of late pregnant women. What is more, there was no correlation between Plt count change and the PCT, MPV and PDW. It is concluded that the changes of hemogram during pregnancy has no correlation with postpartum hemorrhage and blood transfusion in healthy pregnant women, the Plt count and Hb level of pregnant women slightly decline. Nevertheless, PCT, MPV and PDW are within the normal range.