Embryo vascularization by three-dimensional power Doppler ultrasonography at 7-10 weeks of pregnancy

Assess vascular indices of 7-10 week embryos using three-dimensional power Doppler (3DPD) and correlate them with the crown-rump length (CRL).

This cross-sectional study included 65 healthy pregnancies between 7 and 10 weeks. The three-dimensional volume of the embryo was obtained using an endocavitary volumetric transducer and the VOCAL (Virtual Organ Computer-aided Analysis) method, with a 12 degree rotation angle and 15 sequential planes. The vascularization (VI), flow (FI) and the vascular and flow (VFI) indices were obtained using 3DPD and the mean, median, standard deviation, maximum and minimum values were calculated for each gestational age. Pearson's correlation coefficient (r) was used to evaluate the correlation between vascular indices and CRL.

The VI ranged from 0.77 to 41.67, mean 14.68 (+/-8.60), the FI went from 25.71 to 139.50, mean 90.61 (+/-21.51) and the VFI from 0.20 to 81.57, mean 15.69 (+/-12.42). The correlation between CRL and all 3D power Doppler vascular indices was low (VI - r=-0.073, P=0.566; FI - r=0.173, P=0.168 and VFI - r=-0.004, P=0.974).

3D power Doppler vascular indices in 7-10 week embryos do not correlate with CRL.