What are the novel findings of this work? Using the velocity vector imaging speckle-tracking technique, this work revealed reduced measures of ascending aortic elasticity (mean longitudinal strain, global circumferential strain and fractional area change) in fetuses with tetralogy of Fallot (ToF), associated with neonatal aortic annular dilation. What are the clinical implications of this work?Impaired ascending aortic elasticity in the fetal period predicts neonatal aortic annular dilation. The predictive value of reduced measures of ascending aortic elasticity with respect to long-term aortic disease or aorta-related cardiovascular outcomes for patients with ToF is uncertain and should be the subject of further research.