Doppler evaluation of uterine blood flow and pregnancy outcome in patients with URSA：A retrospective cohort study
Authors: Lian Xiaolu , Zhong Yanyu , Lv Xianlin , Lu Sihui , Lu Yaqian , Zhou Ying , Xia Fei 
Published: January 2023

Abstract
Objective
to analyze the uterine artery and spiral artery blood flow parameters in patients with unexplained recurrent spontaneous abortion (URSA) with different pregnancy outcomes, to compare the predictive value of uterine artery and spiral artery blood flow parameters in pregnancy outcome, and to explore the possible mechanism of URSA and the effect of different drug regimens on pregnancy outcome in URSA patients.
Methods
a retrospective cohort study was conducted to analyze the clinical data of 174 pregnant women with unexplained recurrent abortion and 144 pregnant women without adverse pregnancy history. According to the pregnancy outcome, the pregnant women with unexplained recurrent abortion were divided into normal pregnancy outcome group (URSA-N,n = 138) and adverse pregnancy outcome group (URSA-A,n = 36). The pregnant women in the control group were divided into normal pregnancy outcome group (CON-N,n = 129) and adverse pregnancy outcome group (CON-A,n = 15). The blood flow parameters of uterine artery and spiral artery in mid-luteal phase, 11–13 weeks of gestation, 15–17 weeks of gestation and 19–21 weeks of gestation were compared, and the predictive value of uterine artery blood flow parameters and spiral artery blood flow parameters on pregnancy outcome was compared. the effects of aspirin and aspirin combined with low molecular weight heparin on pregnancy outcome in patients with unexplained recurrent abortion were evaluated.
Results
there was no significant difference in age and body mass index (BMI) between URSA group and CON group. The number of spontaneous abortion and BMI in URSA-N group were less than those in URSA-A group. There was no significant difference in age and BMI between CON groups. The spiral artery blood flow parameters of URSA-N group and CON-N group were lower than those of URSA-A group and CON-A group at mid-luteal phase, 11–13 weeks, 15–17 weeks and 19–21 weeks of gestation, respectively. The uterine artery blood flow parameters (mRI, mPI, mS/D) in the middle luteal period, uterine artery pulse index (mPI) at 11–13 weeks of gestation, peak systolic flow rate/diastolic (mS/D) flow rate at 15–17 weeks of gestation in URSA-N group were lower than those in URSA-A group, and the uterine artery blood flow parameters (mRI, mPI, mS/D) of the CON-N group were lower than those of the CON-A group at the middle luteal stage and weeks 11–13 of gestation. The area under the ROC curve of spiral artery blood flow parameters (mRI,mPI,mS/D) was larger than that of uterine artery. There were significant differences in the efficacy of different drugs between the URSA-N group and the URSA-A group, and aspirin combined with low molecular weight heparin could improve the pregnancy outcome.The area under the ROC curve of spiral artery blood flow parameters (mRI,mPI,mS/D) was larger than that of uterine artery. There were significant differences in pregnancy outcomes among different treatment schemes, and aspirin combined with low molecular weight heparin could improve the pregnancy outcome. The area under the ROC curve of spiral artery blood flow parameters (mRI,mPI,mS/D) was larger than that of uterine artery. There were significant differences in the efficacy of different drugs between the URSA-N group and the URSA-A group, and aspirin combined with low molecular weight heparin could improve the pregnancy outcome.
Conclusion
the blood flow parameters (mRI,mPI,mS/D) of uterine artery and spiral artery in adverse pregnancy outcome group are higher than those in normal pregnancy outcome group. Abnormal blood flow parameters of uterine artery and spiral artery may be one of the causes of URSA and adverse pregnancy outcome. Spiral artery blood flow parameters are more valuable than uterine artery blood flow parameters in predicting pregnancy outcome. Aspirin combined with low molecular weight heparin can improve the pregnancy outcome of URSA patients more than aspirin alone.