OC061: Three‐dimensional ultrasound volume calculations of human embryos and young fetuses: a study on volumetry and its reproducibility

Abstract

To evaluate volume measurements with 3D ultrasound in the assessment of human embryos and young fetuses. 44 healthy embryos/fetuses (9 mm CRL—58 mm CRL) were studied. A 7.5 MHz annular array transvaginal 3D-probe was used. Two observers calculated independently from each other the volumes of the bodies and of the limbs. Regression analyses were used to assess the relation between estimated volumes and CRL. The estimated volumes of both observers ranged from mean 93 mm3 at 10 mm CRL to mean 11 169 mm3 at 55 mm CRL. The perceptual share of limbs compared with the mean whole-body volumes increased from 4.7% at CRL 15 mm to 9.3% at CRL 55 mm. Limits of agreement between the observers were −0.12 ± 9.2%. It was possible to reconstruct complex small anatomic structures and thus calculate the volumes of human embryos and fetuses in-vivo by using dedicated 3D-ultrasound equipment. The reproducibility of whole-body volume estimations seemed to be high. Limbs represent a significant share of the fetal body.