Comparison of ultrasonographic and Doppler mapping of the intervillous circulation in normal and abnormal early pregnancies.

Objective: To assess the value of ultrasonography and Doppler imaging in characterizing the intervillous circulation in normal and abnormal early pregnancy.

Design: Cross-sectional study.

Setting: Tertiary care academic hospital.

Patient(s): Eighty-five normal pregnancies and 125 missed miscarriages at 7 to 13 weeks of gestation.

Intervention(s): Grey-scale ultrasonography was used to evaluate the placental anatomy and detect moving echoes inside the intervillous space, and color power Doppler imaging was used to detect continuous venous-like flow in the placental tissue.

Main Outcome Measure(s): Degree of agreement between two investigators for use of grey-scale imaging, comparison of detection of moving echoes in normal and abnormal pregnancies, and comparison of detection of intervillous circulation with grey-scale and color Doppler imaging in abnormal pregnancies.

Result(s): The overall degree of agreement between the two investigators was good. A significantly different distribution of blood flow was found between normal and abnormal pregnancies at 7 to 9 weeks and 10 to 11 weeks but not at 12 to 13 weeks. Intervillous moving echoes were detected by grey-scale imaging significantly more frequently than an intervillous blood flow was detected with color Doppler imaging.

Conclusion(s): In early pregnancy failure, there is a premature and diffuse onset of intervillous blood flow that can be detected by grey-scale imaging. This abnormal blood flow pattern may increase the oxidative stress on the early placental tissue and subsequently impair placental development.