Stillbirth and intrauterine fetal death: factors affecting determination of cause of death at autopsy

Abstract

+A: AbstractObjectives There have been many attempts to classify cause of death in stillbirth, all such systems being subjective, allowing for significant observer bias, making accurate comparisons between systems challenging. The aim of this study was to examine factors relating to determination of cause of death by using a large dataset from two specialist centres, in which observer bias has been reduced by objectively classifying findings and assigning causes of death based on predetermined criteria.Methods Detailed autopsy reports from intrauterine fetal deaths (IUFD) during [2005][2006][2007][2008][2009][2010][2011][2012][2013] in the second and third trimesters were reviewed and findings entered into a specially designed database, in which cause of death (CoD) was assigned using predefined objective criteria. Data regarding CoD categories and factors affecting determination of CoD were analysed through queries and statistical tests run using Microsoft Access, Excel, Graph Pad Prism and StatsDirect, with Mann-Whitney U-test and comparison of proportions testing as appropriate.Results There were 1,064 IUFDs, including 639 stillbirths at >23 weeks' gestation.Overall, around 40% (412 (39%)), had a definite or highly likely cause of death identified, whilst 60% (652) were classified as 'unexplained'. Of these, around half had identified risk factors, or lesions of uncertain significance present, whilst the remaining half (292 (45%)) were entirely unexplained. A stepwise increase in the proportion of unexplained deaths was observed with increasing severity of maceration. Black and Asian women had significantly greater proportions of deaths due to ascending infection whilst women aged over 40 had significantly increased placental-related causes of death. There was no significant difference in cause of death distribution by maternal 3 body mass index or with increasing post-mortem interval. Almost 20% of definitive or likely causes of death could be identified from clinical review or external examination / imaging of the fetus, with most of the remainder being determined following placental examination.Conclusions Based on objective criteria, most IUFDs across gestation remain unexplained despite autopsy examination. The rate of unexplained death varies between 30 and 60% depending on interpretation of the significance of features. The cause of death provided across studies is variable and dependent on both the classification system used and subjective interpretation such that reduction in the proportion of 'unexplained' cases across studies is largely based on speculation around mechanism of death. Novel methods to determine objectively the mechanism of death at postmortem examination are required. 4 +A: IntroductionThe primary aim of postmortem investigation of intrauterine death is determination of cause and mechanism of death, to facilitate counseling of parents, management of subsequent pregnancies and future interventions [1][2][3][4] . Over the last 50 years there have been many attempts to classify cause o...

The prediction of fetal death with a simple maternal blood test at 24-28 weeks: a role for angiogenic index-1 (PlGF/sVEGFR-1 ratio)

“…This syndrome affected 23,595 pregnancies in the United States 7 in 2013, and according to the World Health Organization (WHO), an estimated 2.6 million fetal deaths occurred globally during the third trimester 8, 9 . The most common type of fetal death is unexplained stillbirth 10–13 , which comprises a progressively larger proportion of all fetal deaths as pregnancy advances. This category of fetal death accounts for approximately 20% of all cases just after 20 weeks of gestation and for about 40% of all cases at term 10–15 , while infection and congenital anomalies cause most early fetal deaths (<28 weeks of gestation) 16–19 , placental causes leading to fetal death are more frequent after 26 weeks of gestation 14 including placental vascular underperfusion, resulting in an impaired supply of nutrients to the fetus, 20–35 abruptio placentae 36–38 , and placental senescence that has been implicated as a mechanism of fetal death at term.…”

Post-Mortem Magnetic Resonance Imaging Appearances of Feticide in Perinatal Deaths

“…Within the control group, the cause of death at autopsy was unexplained in 34 (45.3%) cases (in keeping with large observational studies [12]), due to placental abnormalities in 30 (40%) cases, and due to fetal anomalies in 11 (14.7%) cases. Placental causes of death included ascending genital infection (15/30, 50%), placental abruption (4/30, 13.3%), and those relating to placental vascular perfusion (11/30, 36.7%).…”

Effects of intrauterine retention and postmortem interval on body weight following intrauterine death: implications for assessment of fetal growth restriction at autopsy

“…As part of a larger study examining autopsy findings in the investigation of intrauterine death, a dedicated Microsoft Access Autopsy Database (Microsoft Corp., Redmond, WA, USA) was used to collate detailed autopsy and antenatal details from intrauterine deaths examined between 2005 and 2013, inclusive, at Great Ormond Street Hospital and St George's Hospital, London. Every case was reviewed manually and data were extracted according to strict, predefined, objective criteria, separating objective autopsy findings from pathologist interpretations. Data were analyzed through queries and statistical tests using Microsoft Access and Microsoft Excel (Microsoft Corp.), GraphPad Prism (GraphPad Software Inc., San Diego, CA, USA) and Stats Direct (StatsDirect Ltd., Altrincham, UK) software packages.…”