Physiological asymmetry in uterine artery blood flow during the first trimester of pregnancy: New insights from a quantitative assessment using Pulsed-wave color Doppler and M-mode color power angio imaging.

Introduction: This study aimed to quantify uterine artery (UtA) blood flow and its hemodynamic components throughout the first trimester of pregnancy using Doppler ultrasound.

Methods: Cross-sectional cohort study involving women undergoing a routine ultrasound scan between 5 and 13 weeks' gestation. UtA blood flow was measured using Pulsed-wave Color Doppler to assess blood flow velocity across the cardiac cycle and M-mode Color Power Angio imaging to assess UtA diameter.

First-trimester miscarriage rate decreases with hydralazine therapy in pregnancies with early uterine vascular insufficiency: a cohort study.

Background: Miscarriage is the most frequent cause of pregnancy loss, affecting 15-20% of clinically recognized pregnancies. Early uterine vascular insufficiency (EUVI), defined as abnormal uterine artery (UA) Doppler impedance indices in early pregnancy, is present in two-thirds of pregnancies ending in miscarriage after embryonic cardiac activity has been detected. There is currently no available therapy for reducing the risk of miscarriage in these cases.