Stillbirth and intrauterine fetal death: role of routine histological organ sampling to determine cause of death.

OBJECTIVES: Guidelines for the investigation of intrauterine death and sudden unexpected death in infancy (SUDI) recommend, based on expert opinion, autopsy procedures and tissue sampling strategies for histological analysis. Although stillbirth is much more common than SUDI, there have been no large-scale studies published which evaluate the usefulness of histological evaluation of specific organs in stillbirth for determining cause of death. Our aim was to evaluate the use of macroscopic and microscopic assessment of internal organs to determine cause of intrauterine death. METHODS: As part of a larger study evaluating several aspects of autopsy findings in intrauterine death, a dedicated database was used to collate antenatal and postmortem examination details for cases of intrauterine death examined between 2005 and 2013 at two tertiary specialist centers in London, UK. Histological findings for all organs were examined in relation to the final cause of death, as determined by objective criteria. RESULTS: Among 1064 intrauterine deaths, the majority (> 80%) of cases had internal organs that were normal on both macroscopic and microscopic examination. There was no case in which histological cardiac examination provided the cause of death when the macroscopic appearance of the heart was normal. Microscopic examination of lung tissue revealed 13 (1%) cases with histological abnormalities that provided the cause of death when the macroscopic appearance was normal, but there was only one (0.1%) case in which the diagnosis would not have been apparent on placental examination: a case of congenital cytomegalovirus infection. There was no case in which microscopic examination of macroscopically normal liver, kidneys, adrenals, spleen, thymus, intestines, pancreas, brain or thyroid provided the cause of death. CONCLUSION: In this large series of autopsies in cases of intrauterine death, only around 1% of cases demonstrated histological abnormalities which provided the cause of death when the internal organs appeared normal macroscopically. There was no case in which routine histological examination of most tissues provided diagnostically useful information that was not apparent from other examinations, such as placental pathology. There is little benefit, purely in terms of determining cause of death, in obtaining tissue from most macroscopically normal organs for routine histological examination