Difficult Diagnoses in Maternal Death: The Negative Maternal Autopsy

Abstract

A proportion of mothers who die during pregnancy, delivery or some time post-partum, have no clear-cut cause of death despite autopsy examination. Such ‘negative’ autopsies cause pathologists, and all involved in the mother’s care, much concern. They illustrate the frontiers of what is known about why and how critical organs fail, and highlight the variation in the detail to which pathologists investigate maternal deaths. This review is intended for obstetricians, to illustrate the utility and some limitations of autopsy analysis of maternal death. The major scenarios of maternal death where autopsy reveals nothing or only confusing and subtle abnormal morphologies are considered. These include deaths under general and spinal anaesthesia, pulmonary embolism syndromes (air, fat and amniotic fluid), pre-eclampsia-associated deaths, and cardiac deaths including the SADS/MNH syndrome (sudden arrhythmic cardiac death with a morphologically normal heart). Key to the resolution of these post-mortem diagnostic problems is complete gross and histological examination at autopsy, appropriate additional analysis of body fluids and, in some cases, DNA analysis. All this to be correlated with the clinical circumstances and – critically – the patient’s physiological data available around the time the death. Here, a multi-disciplinary input from experts in obstetrics, medicine, intensive care and anaesthesia is invaluable to narrow down the possible pathogeneses and make as accurate a consensus diagnosis as is possible. A major contribution of the autopsy in such cases to exclude alternative possible clinical pathologies. Newer post-mortem examination techniques, such as cadaveric CT scanning, could prove helpful in the future. It is likely that there are clinico-pathological syndromes in maternal death that still await formal identification and characterisation.