Characteristics of midluteal phase uterine artery hemodynamics in patients with recurrent pregnancy loss.

Aim: To study the association in resistance to uterine artery blood flow and recurrent pregnancy loss (RPL) and find its potential influencing factors. Methods: A retrospective study was conducted in 870 RPL and 237 non‐RPL patients visiting to the Clinic from January 2014 to February 2018. All participants underwent comprehensive examinations and were scanned by transvaginal Doppler ultrasonography during the midluteal phase to measure the pulsatility index (PI), resistance index (RI) and systolic/diastolic ratio (S/D) values of the left and right main uterine arteries. P value less than 0.05 was considered statistically significant. Results: The mean PI, RI and S/D values for uterine arteries were significantly higher in RPL patients than in non‐RPL patients (P < 0.001). When subjects were grouped according to the different etiologies of RPL, significant higher indices of uterine arteries were found in RPL patients with antiphospholipid syndrome (P < 0.001), autoimmune diseases (P < 0.001), endocrinological abnormalities (P < 0.05), thrombophilia (P < 0.001), uterine anomalies (P < 0.01) and unexplained RPL (P < 0.001). No differences were found between patients with chromosomal anomalies and uterine arteries blood flow (P > 0.05). In RPL patients, mean PI, mean RI and mean S/D values shows no difference among groups (P > 0.05). The Similar results were observed in age and number of spontaneous abortion (P > 0.05). Conclusion: Impaired uterine artery blood perfusion may be an underlying pathology to RPL, and it can be used as an independent risk factor for pregnancy failure. [ABSTRACT FROM AUTHOR]