Mazzone E, et al. - In view of the proposed higher efficacy of estimating the fetal weight by three-dimensional (3D) ultrasound (US) with fractional thigh volume vs two-dimensional (2D) US particularly within the context of fetuses at risk of macrosomia, researchers compared the accuracy of 2D US vs 3D US with two different methods of projection for the identification of fetal macrosomia at term. In this study, 230 women who were at risk for fetal macrosomia and were referred for fetal biometry between 34⁺⁰-36⁺⁶ weeks were included. Using 2D US and the Hadlock Model IV or through 3D US and the Model VI by Lee et al, they computed the estimated fetal weight (EFW). Observations revealed similar performance of 3D-US-EFW and 2D-US-EFW in the prediction of macrosomia at term; this was observed regardless of the method used for the projection of the EFW. However, on performing the paired comparison between 2D-US-EFW and 3D-US-EFW with either method of projection of the EFW at birth, different properties of the techniques were identified; 2D-US-EFW was associated with higher sensitivity and 3D-US-EFW with higher specificity, PPV and LR +. This finding indicates a potential complementary role of the techniques.