A term male fetus suddenly and unexpectedly died in utero at the 40th week of gestation. The mother had a regular and unremarkable pregnancy except for an anticardiolipin antibodies positivity. The histological examination of the cardiac conduction system showed islands of conduction tissue in the central fibrous body, known as persistent fetal dispersion. The brainstem examination revealed a severe bilateral hypoplasia of the arcuate nucleus. This morphological finding has been described in more than 35% of our stillborn as well as sudden infant death syndrome (SIDS) cases, independently from the presence of anticardiolipin antibodies. Some authors have given emphasis to the possible lethal association of maternal autoantibodies and QT prolongation. Our findings emphasize the need of an accurate postmortem examination including the study of brainstem and cardiac conduction system in every case of unexpected late intrauterine death, following the same standardized autopsy protocol adopted in SIDS cases.