In utero diffusion tensor imaging and tractography was used to depict the structural brain connectome of human fetuses with normal brain morphology. Developmental trajectories of the connectome is illustrated after the k-core decomposition of the structural brain graphs (k=4, number of subjects=60). Top panel: central core of the fetal structural connectome. Bottom panels: development of morphology and core structure in three representative stages during mid and late gestation (19-22. gestational week, 23-28. week and 28-35. week). Visualization was carried out using Paraview, Brainnet Viewer and Slicer 3D.