Analysis of the guidance and predictive value of uterine artery flow parameters in patients with recurrent spontaneous abortion.

Objective: To analyze the uterine artery blood flow parameters of patients with recurrent spontaneous abortion (RSA) at different gestational ages and to investigate the effects of aspirin and low molecular weight heparin (LMWH) on uterine artery blood flow parameters and pregnancy outcomes.
Methods: This was a retrospective cohort study involving analysis of clinical data for 140 patients: 47 in an aspirin group, 49 in a combination group, and 44 in a control group. The uterine artery blood flow parameters of the three groups in the middle luteal period and 10th, 12th, 16th, and 20th gestational weeks were compared. Trends in uterine artery flow parameters were predicted by function fitting, and the uterine artery flow parameters and pregnancy outcomes between different drug administration regimens were compared.
Results: With increasing gestational age, the uterine artery blood flow parameters of the three groups gradually decreased. In the middle luteal phase, the uterine artery blood flow parameters (mRI, mPI, mS/D) of the recurrent spontaneous abortion group, that is, the aspirin and combination groups, were significantly higher than those of the control group. Uterine artery blood flow parameters from 10 to 20 weeks of gestation were as follows: combined group < aspirin group < normal pregnancy group. The mean resistance index (mRI) in the combination group decreased most rapidly compared with the aspirin group between 10 and 20 weeks of gestation. The live birth rate was higher in the combination group than in the aspirin group.
Conclusions: Both aspirin and aspirin combined with LMWH can reduce uterine artery blood flow parameters, and combination therapy is superior to aspirin alone. In the RSA group, the rate of mRI decline may predict pregnancy outcome to some extent. Combination therapy can improve the live birth rate and reduce the miscarriage rate.
(© 2022 The Authors. Journal of Obstetrics and Gynaecology Research published by John Wiley & Sons Australia, Ltd on behalf of Japan Society of Obstetrics and Gynecology.)