This review addresses, from the pathologist’s perspective, the issue of unexplained stillbirth, a tragic event that is about six to eight-fold more frequent than SIDS. In particular, our studies performed on a wide set of ante-partum victims have contributed to identify the nature and frequency of alterations of the central autonomic nervous system, and particularly of structures of the brainstem and cerebellum controlling the vital functions, that may provide a deeper insight into specific mechanisms leading to intrauterine death. In addition, we support the hypothesis of a close relation between maternal cigarette smoking, as well as exposure to air pollutants during pregnancy, and abnormal human brain development processes.