Motor vehicle collisions are an important cause of blunt abdominal trauma in pregnant woman. Among the possible outcomes of blunt abdominal trauma, placental abruption, direct fetal trauma, and rupture of the gravid uterus are described. An interesting case of complete fetal decapitation with uterine rupture due to a high-velocity motor vehicle collision is described. The external examination of the fetus showed a disconnection between the cervical vertebrae C3 and C4. The autopsy examination showed hematic infiltration of the epicranic soft tissues, an overlap of the parietal bones, and a subarachnoid hemorrhage in the posterior part of interparietal area. Histological analysis was carried out showing a lack of epithelium and hemorrhages in the subcutaneous tissue, a hematic infiltration between the muscular fibers of the neck and between the collagen and deep muscular fibers of the tracheal wall. Specimens collected from the placenta and from the uterus showed a hematic infiltration with hypotrophy of the placental villi, fibrosis of the mesenchymal villi with ischemic phenomena of the membrane. The convergence of circumstantial data, autopsy results, and histological data led us to conclude that the neck lesion was vital and the cause of death was attributed to the motor vehicle collision.