RESUMEN
The corpus callosum (CC) is a thick band of nerve fibers that divides the cerebral cortex lobes into the left and right hemispheres. Prenatal diagnosis of corpus callosum agenesis (partial/total) has been described frequently in the literature. In this case report, a case of corpus callosum dysplasia with different development of the halves of the corpus callosum in the right and left brain hemispheres, which was not previously discussed in the literature, will be described. Whenever we have any doubts about CC, axial, coronal, and sagittal scans of the fetal brain should be performed with TVUSG (transvaginal ultrasonography) or TAUSG (transabdominal ultrasonography) according to the position of the fetal head, and both length and thickness should be measured.