Maternal Deaths from Amniotic-Fluid Embolism: in Correlation with Clinical and Histopathological Findings

The present study demonstrates the significance of autopsy in cases of maternal deaths in elucidating the cause of death due to Amniotic fluid embolism; and to corroborate the pathological, microscopic and clinical features of such deaths. A retrospective five year cross-sectional study on 24 fatal cases of amniotic fluid embolism, confirmed by autopsy findings, clinical features and post-mortem histopathological reports; and, was conducted at our department of Forensic Medicine and Toxicology during the period 2007-2012. It showed that the majority (88%) of cases died due to amniotic fluid embolism were married, multiparous women; and had 1-3 uneventful past-pregnancies each. Eighteen cases had normal antenatal histories. In all cases, the clinical onset was sudden and unexpected, having occurred during the first stage of labour in 12 cases, and being associated with convulsions in eight. Seventeen cases showed features of coagulopathy, with 14 cases of disseminated intravascular coagulation (DIC). Overall foetal survival rate was poor. Seven cases were associated with induction of labour, while another 6 occurred after augmentation. Emergency caesarean sections were performed in 9 cases. Autopsy demonstrated moderate to severe pulmonary edema in 22 cases, accompanied by pulmonary hemorrhage in 16 cases. Coronary atheroma was seen in 15 cases, with 6 cases showing subendocardial hemorrhage. Significant utero-cervical injuries were found in 9 cases. The median survival time is 6 hours. Microscopic observation demonstrated the presence of squamous epithelial cell emboli within the pulmonary vasculature in all cases; seven cases showed fibrin microthrombi (DIC), alveolar and pulmonary interstitial inflammation, focal myocardial and hepatocellular necrosis, and myocardial interstitial inflammation. It can be concluded that amniotic fluid embolism is a sudden, unexpected, of course relatively rare cause of maternal death. Multiparous mothers in third decade of their life are vulnerable of developing it during labour, but may have post-partum presentation too; and, the mortality rate is relatively rapid, usually within 12 hour..