The role of shear wave elastography in the assessment of placentas in healthy pregnancy women during third-trimester: A preliminary study

The study aimed to analysis the elasticity value of placenta in healthy women during third trimester by shear wave elastography (SWE), and tried to investigate the relationship between clinical characteristics and placental elasticity.Singleton healthy pregnant women who had routine ultrasound examination between 28 and 37 weeks were enrolled. SWE of the frontier placentas were evaluated by transabdominal ultrasound elastography. Only placentas at front wall were enrolled. The placenta was divided into three areas for SWE examination: the central area (Area A), the periphery area (Area B) and the area between central and edge of placenta (Area C). Then, the subjects with normal delivery were evaluated and analyze the relationship between clinical features and placental elasticity.A total of 43 pregnant women were included in this study. The mean value of SWE in the central area was 5.67±2.51 kPa. And it was 6.50±2.57 kPa in the periphery area, 5.17±2.25 kPa in the area C. There were no significant differences except area B and C. In different age group, there were no significant differences except area C. The history of childbearing and uterine operation and the gestational age were no significant correlation with the SWE value of placenta. There were also no significant differences between birth weight percentile and placental elasticity.The placental elasticity is stable in healthy women during third trimester. Shear wave elastography is helpful to assess the placental elasticity and can be used as a supplemental technique to existing methods for monitoring the placental function. But the normal elasticity range in some certain areas of placenta should be confirmed by further study.