Objective:To investigate the relationship between uterine artery blood flow parameters detected by ultrasound examination during early pregnancy and pregnancy outcomes in pregnant women who had a history of recurrent spontaneous abortion.Methods:A total of 100 pregnant women with a history of recurrent spontaneous abortion who were at 6-10 weeks of gestation and received treatment in Zhuji Maternal and Child Health Hospital from June 2020 to June 2022 were included in the study group. Using a case-control study method, 100 normal pregnant women who were at 6-10 weeks of gestation who concurrently underwent physical examination were selected and included in the control group. Both groups of pregnant women were tested for uterine artery blood flow parameters using color Doppler ultrasound diagnostic equipment, including peak systolic/diastolic velocity (S/D), resistance index (RI), and pulsatility index (PI). The occurrence of early miscarriage was monitored in both groups. The value of uterine artery blood flow parameters in the prediction of adverse pregnancy outcomes and the correlation between uterine artery blood flow parameters and adverse pregnancy outcomes were analyzed. Multivariate logistic regression was performed to analyze the relationship between uterine artery blood flow parameters and adverse pregnancy outcomes.Results:S/D, RI, and PI in the study group were (3.87 ± 0.43), (0.93 ± 0.16), and (1.73 ± 0.41), respectively, which were significantly higher than (2.54 ± 0.37), (0.64 ± 0.14), and (1.24 ± 0.35) in the control group ( t = 23.44, 13.64, 9.09, all P < 0.05). The early abortion rate in the study group was 57.0% (57/100), which was significantly higher than 2.0% (2/100) in the control group ( χ2 = 72.73, P < 0.05). The receiver operating characteristic curve analysis showed that S/D sensitivity and specificity in the prediction of adverse pregnancy outcomes were 79.1% and 70.2%, respectively, RI sensitivity and specificity were 88.4% and 84.2%, respectively, and PI sensitivity and specificity were 65.1% and 75.4%, respectively. Pearson analysis results showed that S/D, RI, and PI were positively linearly correlated with adverse pregnancy outcomes ( r = 0.587, 0.648, 0.613, all P < 0.05). Conclusion:Uterine artery blood flow parameters S/D, RI, and PI are abnormally high in pregnant women with a history of recurrent spontaneous abortion in the early stage of pregnancy. These parameters are closely associated with adverse pregnancy outcomes and are the independent risk factors of adverse pregnancy outcomes.