The role of fetal autopsy and placental examination in the causes of fetal death: a retrospective study of 132 cases of stillbirths

The placenta in fetal death: molecular evidence of dysregulation of inflammatory, proliferative, and fetal protective pathways

BACKGROUND

It is estimated that over 2 million cases of fetal death occur worldwide every year, but, despite the high incidence, several basic and clinical characteristics of this disorder are still unclear. Placenta is suggested to play a central role in fetal death. Placenta produces hormones, cytokines and growth factors that modulate functions of the placental-maternal unit. Fetal death has been correlated with impaired secretion of some of these regulatory factors.

OBJECTIVE

The aim of the present study was to evaluate, in placentas collected from fetal death, the gene expression of inflammatory, proliferative and protective factors.

STUDY DESIGN

Cases of fetal death in singleton pregnancy were retrospectively selected, excluding pregnancies complicated by fetal anomalies, gestational diabetes, intrauterine growth restriction and moderate to severe maternal diseases. A group of placentas collected from healthy singleton term pregnancies were used as controls. Groups were compared regarding maternal and gestational age, fetal sex and birthweight. Placental messenger RNA expression of inflammatory (interleukin 6), proliferative (activin A, transforming growth factor β1) and regulatory (vascular endothelial growth factor, vascular endothelial growth factor receptor 2, ATP-binding cassette transporters (ABC) ABCB1 and ABCG2, sphingosine 1-phosphate signaling pathway) markers was conducted using real-time polymerase chain reaction. Statistical analysis and graphical representation of the data were performed using the GraphPad Prism 5 software. For the statistical analysis, Student's t test was used, and P values<.05 were considered significant.

RESULTS

Placental mRNA expression of interleukin 6 and vascular endothelial growth factor receptor 2 resulted significantly higher in the fetal death group compared to controls (P<.01), while activin A, ABCB1, and ABCG2 expression resulted significantly lower (P<.01). A significant alteration in the sphingosine 1-phosphate signaling pathway was found in the fetal death group, with an increased expression of the specific receptor isoforms sphingosine 1-phosphate receptor 1, 3, and 4 (sphingosine 1-phosphate1, sphingosine 1-phosphate3, sphingosine 1-phosphate4) and of sphingosine kinase 2, 1 of the enzyme isoforms responsible for sphingosine 1-phosphate synthesis (P<.01).

CONCLUSION

The present study confirmed a significantly increased expression of placental interleukin 6 and vascular endothelial growth factor receptor 2 mRNA, and for the first time showed an increased expression of sphingosine 1-phosphate receptors and sphingosine kinase 2 as well as a decreased expression of activin A and of selected ATP-binding cassette transporters, suggesting that multiple inflammatory and protective factors are deranged in placenta of fetal death.

Identifying causes and associated factors of stillbirths using autopsy of the fetus and placenta

PURPOSE

The study aimed to evaluate the causes of death and associated factors in cases of stillbirth, using post-mortem examination and applying a rigorous, evidence-based holistic approach.

METHODS

Our retrospective observational study included cases of autopsy following stillbirth that occurred at our tertiary medical center during a period of 8 years. Detailed up-to-date criteria that incorporate clinical reports, medical history, prenatal imaging, and histopathological findings were used to evaluate the cause of death and associated factors.

RESULTS

After applying our proposed methodology, 138 cases of stillbirth were classified into eight categories based on the causes of death. A definitive cause of death was observed in 100 (72%) cases, while 38 (28%) cases were considered unexplained. The leading cause of death was placental lesions (n = 39, 28%) with maternal vascular malperfusion (MVM) lesions being the most common (54%). Ascending infection was the second most common cause of fetal death (n = 24, 17%) and was often seen in the setting of preterm labor and cervical insufficiency.

CONCLUSION

The largest category of cause of death was attributed to placental pathology. Using rigorous detailed up-to-date criteria that incorporate pathological and clinical factors may help in objectively classifying the cause of death.

Data usefulness in determining cause of stillbirth in South Asia

OBJECTIVE

To evaluate the usefulness of data to determine cause of stillbirth in India and Pakistan.

DESIGN

Prospective, observational study.

SETTINGS

Study hospitals in India and Pakistan.

POPULATION

200 fetal deaths with placental evaluation and minimally invasive tissue sampling (MITS) of internal organs and polymerase chain reaction (PCR) test for 75 pathogens.

MAIN OUTCOME MEASURES

Data defined as useful to determine stillbirth causes.

RESULTS

Placental pathology was the most useful to determine cause of stillbirth. Comparing placental and fetal weight with standard weights was useful in 44.5% and 48.5%, respectively. Lung histology was useful in 42.5%. Most of the other findings of internal organ histology were only occasionally useful. Signs of abruption, by maternal history or placental evaluation, were always deemed useful. Placenta, brain and cord blood PCR were also useful, but less often than histology.

CONCLUSION

Based on this analysis, maternal clinical history, placental histology and fetal examination were most informative. Comparing the placental and fetal weights with recognised standards was useful in nearly half the cases. Fetal tissue histology and PCR were also informative. Of all the potential tests of MITS-obtained specimens, we would first recommend histological evaluation of the lungs, and using a multiplex PCR platform would determine pathogens in blood and brain/CSF. We recognise that this approach will not identify some causes, including some genetic and internal organ anomalies, but will confirm most common causes of stillbirth and most of the preventable causes of stillbirth in low- and middle-income countries.

Interventions, outcomes and outcome measurement instruments in stillbirth care research: A systematic review to inform the development of a core outcome set

BACKGROUND

A core outcome set could address inconsistent outcome reporting and improve evidence for stillbirth care research, which have been identified as an important research priority.

OBJECTIVES

To identify outcomes and outcome measurement instruments reported by studies evaluating interventions after the diagnosis of a stillbirth.

SEARCH STRATEGY

Amed, BNI, CINAHL, ClinicalTrials.gov, Cochrane Central Register of Controlled Trials, Cochrane Database of Systematic Reviews, Embase, MEDLINE, PsycINFO, and WHO ICTRP from 1998 to August 2021.

SELECTION CRITERIA

Randomised and non-randomised comparative or non-comparative studies reporting a stillbirth care intervention.

DATA COLLECTION AND ANALYSIS

Interventions, outcomes reported, definitions and outcome measurement tools were extracted.

MAIN RESULTS

Forty randomised and 200 non-randomised studies were included. Fifty-eight different interventions were reported, labour and birth care (52 studies), hospital bereavement care (28 studies), clinical investigations (116 studies), care in a multiple pregnancy (2 studies), psychosocial support (28 studies) and care in a subsequent pregnancy (14 studies). A total of 391 unique outcomes were reported and organised into 14 outcome domains: labour and birth; postpartum; delivery of care; investigations; multiple pregnancy; mental health; emotional functioning; grief and bereavement; social functioning; relationship; whole person; subsequent pregnancy; subsequent children and siblings and economic. A total of 242 outcome measurement instruments were used, with 0-22 tools per outcome.

CONCLUSIONS

Heterogeneity in outcome reporting, outcome definition and measurement tools in care after stillbirth exists. Considerable research gaps on specific intervention types in stillbirth care were identified. A core outcome set is needed to standardise outcome collection and reporting for stillbirth care research.

Toward a new taxonomy of obstetrical disease: improved performance of maternal blood biomarkers for the great obstetrical syndromes when classified according to placental pathology

BACKGROUND

The major challenge for obstetrics is the prediction and prevention of the great obstetrical syndromes. We propose that defining obstetrical diseases by the combination of clinical presentation and disease mechanisms as inferred by placental pathology will aid in the discovery of biomarkers and add specificity to those already known.

OBJECTIVE

To describe the longitudinal profile of placental growth factor (PlGF), soluble fms-like tyrosine kinase-1 (sFlt-1), and the PlGF/sFlt-1 ratio throughout gestation, and to determine whether the association between abnormal biomarker profiles and obstetrical syndromes is strengthened by information derived from placental examination, eg, the presence or absence of placental lesions of maternal vascular malperfusion.

STUDY DESIGN

This retrospective case cohort study was based on a parent cohort of 4006 pregnant women enrolled prospectively. The case cohort of 1499 pregnant women included 1000 randomly selected patients from the parent cohort and all additional patients with obstetrical syndromes from the parent cohort. Pregnant women were classified into six groups: 1) term delivery without pregnancy complications (n=540; control); 2) preterm labor and delivery (n=203); 3) preterm premature rupture of the membranes (n=112); 4) preeclampsia (n=230); 5) small-for-gestational-age neonate (n=334); and 6) other pregnancy complications (n=182). Maternal plasma concentrations of PlGF and sFlt-1 were determined by enzyme-linked immunosorbent assays in 7560 longitudinal samples. Placental pathologists, masked to clinical outcomes, diagnosed the presence or absence of placental lesions of maternal vascular malperfusion. Comparisons between mean biomarker concentrations in cases and controls were performed by utilizing longitudinal generalized additive models. Comparisons were made between controls and each obstetrical syndrome with and without subclassifying cases according to the presence or absence of placental lesions of maternal vascular malperfusion.

RESULTS

1) When obstetrical syndromes are classified based on the presence or absence of placental lesions of maternal vascular malperfusion, significant differences in the mean plasma concentrations of PlGF, sFlt-1, and the PlGF/sFlt-1 ratio between cases and controls emerge earlier in gestation; 2) the strength of association between an abnormal PlGF/sFlt-1 ratio and the occurrence of obstetrical syndromes increases when placental lesions of maternal vascular malperfusion are present (adjusted odds ratio [aOR], 13.6 vs 6.7 for preeclampsia; aOR, 8.1 vs 4.4 for small-for-gestational-age neonates; aOR, 5.5 vs 2.1 for preterm premature rupture of the membranes; and aOR, 3.3 vs 2.1 for preterm labor (all P<0.05); and 3) the PlGF/sFlt-1 ratio at 28 to 32 weeks of gestation is abnormal in patients who subsequently delivered due to preterm labor with intact membranes and in those with preterm premature rupture of the membranes if both groups have placental lesions of maternal vascular malperfusion. Such association is not significant in patients with these obstetrical syndromes who do not have placental lesions.

CONCLUSION

Classification of obstetrical syndromes according to the presence or absence of placental lesions of maternal vascular malperfusion allows biomarkers to be informative earlier in gestation and enhances the strength of association between biomarkers and clinical outcomes. We propose that a new taxonomy of obstetrical disorders informed by placental pathology will facilitate the discovery and implementation of biomarkers as well as the prediction and prevention of such disorders.

Value of Placental Examination in the Diagnostic Evaluation of Stillbirth

ObjectiveThe aim was to assess the contribution of placental examination in the etiologic investigation of stillbirth. Materials and Methods: A retrospective review of stillbirths that occurred after 14 weeks gestation was conducted for a one-year period. Twin pregnancies and fetuses without placentas were excluded. According to the fetoplacental examination, stillbirths were classified into etiologic groups. Results: A total of 147 stillbirths were selected. They were associated with placental, materno-fetal, fetal and multiple causes in 89 cases (61%), 23 cases (16%), 14 cases (9%) and 13 cases (9%), respectively. Unexplained stillbirths were observed in 8 cases (5%). Placental abnormalities were identified in 132/147 cases (90%). They were consistent with vascular, inflammatory and developmental lesions in 82/132 cases (61%), 28/132 cases (21%) and 18/132 cases (13%), respectively. Conclusion: Placental lesions were the main causes of stillbirth and were predominantly of vascular type including chronic villous hypoxia-ischemia and funicular anomalies.

A retrospective autopsy study of 42 cases of stillbirth in Avicenna Research Institute

BACKGROUND

According to the World Health Organization about 2.6 million deaths were reported worldwide in 2015. More than 98% of stillbirths occur in developing countries. At present, the causes of many cases of stillbirth are unknown due to the lack of necessary data and autopsies in Iran. The aim of this study was to investigate the most plausible cause of stillbirth by evaluating clinical records and autopsies.

METHODS

A cross-sectional study of 42 stillbirth autopsies in Avicenna Research Institute from 2012 to 2019, was conducted. Data were extracted from a checklist prepared by the project researchers. The checklist contains maternal demographic information, medical history and maternal illness, pregnancy risk factors, placenta and stillbirth information. Collected data were reviewed and classified according to the ReCoDe (Relevant Condition at Death) system.

RESULTS

In the present study, based on ReCoDe classification, related causes of 95.2% of stillbirths were identified and 4.8% were in the unclassified group. The most common causes were: Fetal causes (64.3%), umbilical cord (14.3%), placenta (7.1%), amniotic fluid (4.8%), maternal medical conditions (2.4%). The causes of about 70% of stillbirth in Iran are unexplained, but in this study, using autopsy results and ReCoDe classification, only 4.8% of stillbirth causes remained unexplained.

CONCLUSIONS

In our study, unknown cases were rare after autopsy. But considering the limitations and costs of autopsy, we need to design the guideline to specify cases who need an autopsy. Fetal autopsy, placental examination and clinical information could reduce the proportion of stillbirths that remain unexplained.

A comparison of three classification systems for stillbirth

BACKGROUND

Understanding the causes of perinatal death can provide relevant information to couples, caregivers, and society. Classification systems play a crucial role in identifying the most relevant conditions suggesting preventive measures for decreasing stillbirth (SB). In 2016 the International Classification of Disease to Deaths during the Perinatal Period (ICD-PM) was released with the aim to suggest a universally accepted classification.

METHODS

This is a prospective cohort study that enrolled all SBs occurred in Emilia-Romagna, from 2014 to 2017. We prospectively applied ReCoDe classification and retrospectively used Simplified CODAC classification and ICD-PM. The aim of this study is to compare different classification systems on a cohort of SBs, undergoing a comprehensive workup, to establish what classification minimizes rates of unexplained SB.

RESULTS

We registered 443 SBs. According to ReCoDe the largest category of SB was "placental insufficiency/infarction" (16.9%), followed by "abruptio placentae" (14.2%). Unexplained cases are 16.7%. Gestational age <37 weeks is less frequent in the group of women with unclassified SB (OR 0.50, OR95%CI [0.3-0.8]) against women with classified SB. Considering CODAC the two largest categories are "infarctions or thrombi" (16.3%) and "abruption or retro-placental haematoma" (15.1%), instead only 17.2% of cases remained unexplained.

CONCLUSIONS

Comparing ReCoDe and CODAC we found no real difference in any category. ReCoDe and CODAC better underlines the primary cause of death. ICD-PM reveals to be easily applicable to clinical practice. ICD-PM has the lowest rate of unexplained SBs (9.3%) due to the structure itself and not to a deeper comprehension of death.

Benefits and Limitations of the Minimally Invasive Postmortem: A Review of an Innovative Service Development

INTRODUCTION

Pediatric postmortem (PM) rates have significantly declined, creating a need for effective minimally invasive alternatives to correlate with parental wishes. We review the use of a minimally invasive fetal and neonatal PM service further to preliminary findings published in 2015.

MATERIALS AND METHODS

Cases taken from the mortuary electronic database from 2012 to 2017 are analyzed. The minimally invasive service consisted primarily of external examination, magnetic resonance imaging (MRI), and placental examination. Any significant conditions found noted. All pathology reports include a Relevant Condition at Death (ReCoDe) obstetric classification. Reports analyzed to determine which aspects of the service provided positive information.

RESULTS

Of 1498 perinatal postmortems, 105 (7%) were PM MRI, of which 75.24% were intrauterine fetal deaths. Relevant conditions were identified in 94 cases (89.52%), and ReCoDe categories in 80 cases (76.19%). Moreover, 90% of cases had a ReCoDe condition, with 10% unclassified. Seven cases had more than 1 ReCoDe. Main conditions related to placenta (32.5%) and umbilical cord (27.5%). The most informative elements were placental examination and MRI.

CONCLUSION

Minimally invasive PMs are a viable alternative to traditional autopsy when this option is refused. However, further case analysis is needed to determine potential bias toward certain classification codes.

Disorders of placental villous maturation in fetal death

Objective The aims of this study were to ascertain the frequency of disorders of villous maturation in fetal death and to also delineate other placental histopathologic lesions in fetal death. Methods This was a retrospective observational cohort study of fetal deaths occurring among women between January 2004 and January 2016 at Hutzel Women's Hospital, Detroit, MI, USA. Cases comprised fetuses with death beyond 20 weeks' gestation. Fetal deaths with congenital anomalies and multiple gestations were excluded. Controls included pregnant women without medical/obstetrical complications and delivered singleton, term (37-42 weeks) neonate with 5-min Apgar score ≥7 and birthweight between the 10th and 90th percentiles. Results Ninety-two percent (132/143) of placentas with fetal death showed placental histologic lesions. Fetal deaths were associated with (1) higher frequency of disorders of villous maturation [44.0% (64/143) vs. 1.0% (4/405), P < 0.0001, prevalence ratio, 44.6; delayed villous maturation, 22% (31/143); accelerated villous maturation, 20% (28/143); and maturation arrest, 4% (5/143)]; (2) higher frequency of maternal vascular malperfusion lesions [75.5% (108/143) vs. 35.7% (337/944), P < 0.0001, prevalence ratio, 2.1] and fetal vascular malperfusion lesions [88.1% (126/143) vs. 19.7% (186/944), P < 0.0001, prevalence ratio, 4.5]; (3) higher frequency of placental histologic patterns suggestive of hypoxia [59.0% (85/143) vs. 9.3% (82/942), P < 0.0001, prevalence ratio, 6.8]; and (4) higher frequency of chronic inflammatory lesions [53.1% (76/143) vs. 29.9% (282/944), P < 0.001, prevalence ratio 1.8]. Conclusion This study demonstrates that placentas of women with fetal death were 44 times more likely to present disorders of villous maturation compared to placentas of those with normal pregnancy. This suggests that the burden of placental disorders of villous maturation lesions is substantial.

CD34 immunostain increases the sensitivity of placental diagnosis of fetal vascular malperfusion in stillbirth

INTRODUCTION

Postmortem regressive placental changes of stillbirth may obscure the pre-existing placental histomorphology. The objective is to find out whether the use of CD34 immunostain can increase the sensitivity of placental examination in the diagnosis of fetal vascular malperfusion (FVM).

METHODS

Twenty six independent clinical and 46 placental variables of 46 placentas from stillbirths were statistically compared to those of 92 placentas from livebirths. One histologically most unremarkable section per case was stained using double E-cadherin/CD34 immunostain (ECCD34). Clusters of avascular/hypovascular chorionic villi on hematoxylin and eosin (H&E) staining system and/or CD34 immunostaining, the latter also including endothelial CD34 positive debris in the villous stroma, were regarded as evidence of FVM.

RESULTS

The gestational age and cesarean section rate were statistically significantly lower and the induction of labor and mild erythroblastosis of fetal blood was higher, but the frequencies of clinical and placental features of umbilical cord compromise were not statistically significant between stillbirths and livebirths, respectively. By using H&E stain, 9 (19.6%) of stillbirths and 30 (32.6%) of livebirths showed clusters of avascular villi on H&E. By CD34, the rates of FVM increased to 23 (50%) and 34 (40%), respectively. The increase was statistically significant for stillbirths only (Chi square = 9.4, p = 0.002). By CD34, new clusters of hypovascular chorionic villi or villi with endothelial fragmentation were found in 23 stillbirth cases (50%) as opposed to livebirths (29 cases, 31.5%)(Chi square = 9.4, p = 0.002).

DISCUSSION

When compared with H&E stain, the CD34 increases sensitivity and/or upgrades FVM in placental examination in stillbirths but not in livebirths.

The prediction of fetal death with a simple maternal blood test at 20-24 weeks: a role for angiogenic index-1 (PlGF/sVEGFR-1 ratio)

BACKGROUND

Fetal death is an obstetrical syndrome that annually affects 2.4 to 3 million pregnancies worldwide, including more than 20,000 in the United States each year. Currently, there is no test available to identify patients at risk for this pregnancy complication.

OBJECTIVE

We sought to determine if maternal plasma concentrations of angiogenic and antiangiogenic factors measured at 24-28 weeks of gestation can predict subsequent fetal death.

STUDY DESIGN

A case-cohort study was designed to include 1000 randomly selected subjects and all remaining fetal deaths (cases) from a cohort of 4006 women with a singleton pregnancy, enrolled at 6-22 weeks of gestation, in a pregnancy biomarker cohort study. The placentas of all fetal deaths were histologically examined by pathologists who used a standardized protocol and were blinded to patient outcomes. Placental growth factor, soluble endoglin, and soluble vascular endothelial growth factor receptor-1 concentrations were measured by enzyme-linked immunosorbent assays. Quantiles of the analyte concentrations (or concentration ratios) were estimated as a function of gestational age among women who delivered a live neonate but did not develop preeclampsia or deliver a small-for-gestational-age newborn. A positive test was defined as analyte concentrations (or ratios) <2.5th and 10th centiles (placental growth factor, placental growth factor/soluble vascular endothelial growth factor receptor-1 [angiogenic index-1] and placental growth factor/soluble endoglin) or >90th and 97.5th centiles (soluble vascular endothelial growth factor receptor-1 and soluble endoglin). Inverse probability weighting was used to reflect the parent cohort when estimating the relative risk.

RESULTS

There were 11 fetal deaths and 829 controls with samples available for analysis between 24-28 weeks of gestation. Three fetal deaths occurred <28 weeks and 8 occurred ≥28 weeks of gestation. The rate of placental lesions consistent with maternal vascular underperfusion was 33.3% (1/3) among those who had a fetal death <28 weeks and 87.5% (7/8) of those who had this complication ≥28 weeks of gestation. The maternal plasma angiogenic index-1 value was <10th centile in 63.6% (7/11) of the fetal death group and in 11.1% (92/829) of the controls. The angiogenic index-1 value was <2.5th centile in 54.5% (6/11) of the fetal death group and in 3.7% (31/829) of the controls. An angiogenic index-1 value <2.5th centile had the largest positive likelihood ratio for predicting fetal death >24 weeks (14.6; 95% confidence interval, 7.7-27.7) and a relative risk of 29.1 (95% confidence interval, 8.8-97.1), followed by soluble endoglin >97.5th centile and placental growth factor/soluble endoglin <2.5th, both with a positive likelihood ratio of 13.7 (95% confidence interval, 7.3-25.8) and a relative risk of 27.4 (95% confidence interval, 8.2-91.2). Among women without a fetal death whose plasma angiogenic index-1 concentration ratio was <2.5th centile, 61% (19/31) developed preeclampsia or delivered a small-for-gestational-age neonate; when the 10th centile was used as the cut-off, 37% (34/92) of women had these adverse outcomes.

CONCLUSION

(1) A maternal plasma angiogenic index-1 value <2.5th centile (0.126) at 24-28 weeks of gestation carries a 29-fold increase in the risk of subsequent fetal death and identifies 55% of subsequent fetal deaths with a false-positive rate of 3.5%; and (2) 61% of women who have a false-positive test result will subsequently experience adverse pregnancy outcomes.

Fetal death: an extreme manifestation of maternal anti-fetal rejection

OBJECTIVE

The aim of this study was to determine the association between chronic placental inflammation and amniotic fluid (AF) markers of maternal anti-fetal rejection as well as the presence of microorganisms in the AF fluid of patients with fetal death.

STUDY DESIGN

This cohort study included 40 patients with fetal death whose placentas were examined for chronic inflammatory lesions and whose AF chemokine ligand (CXCL)10 and interleukin (IL)-6 concentrations were determined by immunoassays. AF was processed for bacteria, mycoplasmas and viruses using cultivation and molecular microbiologic techniques (i.e. PCR-ESI/MS).

RESULTS

(1) The most prevalent placental findings were maternal vascular underperfusion (63.2%, 24/38), followed by chronic inflammatory lesions (57.9%, 22/38); (2) chronic chorioamnionitis (18/38) was three times more frequent than villitis of unknown etiology (6/38); (3) an elevated AF CXCL10 concentration (above the 95th centile) was present in 60% of the cases, and a receiver operating characteristics (ROC)-derived cut-off of 2.9 ng/mL had a sensitivity of 73% and a specificity of 75% in the identification of chronic placental inflammatory lesions; (4) only five cases had microbial invasion of the amniotic cavity, and the presence of microorganisms did not correlate with chronic placental inflammation.

CONCLUSION

In women with unexplained fetal death, there is an association between elevated AF CXCL10 and chronic placental inflammatory lesions. Therefore, we conclude that a subset of patients with fetal death may have endured a breakdown of maternal-fetal tolerance, which cannot be attributed to microorganisms in the amniotic cavity.

Causes of Stillbirth in Turku, Finland, 2001-2011

The objective of the study was to examine the causes of stillbirth in the district of Southwest Finland and to assess the importance of postmortem examination and the selection of a suitable classification system for classifying stillbirths. This study is a cohort study where the fetal autopsies were performed in the Department of Pathology at Turku University Hospital, Finland, 2001-2011. Stillbirths from singleton pregnancies at the gestational age of ≥ 24 + 0 weeks (if unknown, gestational weight ≥ 500 g) (n = 98) were selected. In addition, stillbirths from multiple gestations (n = 6) were also analyzed. The causes of stillbirths were classified according to the Relevant Condition at Death classification system. Maternal risk factors and the role of fetal gestational age and weight for the causes of stillbirth were assessed. The most common causes of singleton stillbirth were lethal congenital anomalies, placental insufficiencies, and constricting loops and knots of the umbilical cord. The cause of singleton stillbirth could be determined for 78% of the cases, leaving 22% unclassified. There were no significant differences in the causes of stillbirth by gestational age or weight. Smoking may increase the incidence of placental abruption ( P < 0.01). The most common causes of stillbirth in Turku, Finland, are consistent with findings from other high-income countries. With careful postmortem examination and ancillary studies, it is possible to find the cause of stillbirth for most of the cases. Even if the stillbirth is left unexplained, many other harmful conditions can be excluded thus benefiting both the parents and the health care unit.

Stillbirth and intrauterine fetal death: role of routine histopathological placental findings to determine cause of death

OBJECTIVES

Placental abnormalities are a common cause of death in stillbirth, ranking second only to unexplained deaths, though there is wide variation in the proportion attributed to placental disease. In clinical practice, interpretation of the significance of placental findings is difficult, since many placental features in stillbirths overlap with those in live births. Our aim was to examine objectively classified placental findings from a series of > 1000 autopsies following intrauterine death in order to evaluate the role of placental histological examination in determining the cause of 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 all cases examined between 2005 and 2013 at two tertiary specialist centers in London, UK. Histological findings for placentas were evaluated in relation to the final cause of death.

RESULTS

Among 1064 intrauterine deaths, 946 (89%) cases had the placenta submitted for examination as part of the autopsy. Of these, 307 (32%) cases had the cause of death assigned to abnormalities of the placenta, cord or membranes. Around one third of stillbirths (≥ 24 weeks) had some isolated placental histological abnormality identified, many of uncertain significance, a significantly greater proportion than in cases of second-trimester intrauterine fetal demise (P < 0.0001). The cause of death was ascending infection in 176/946 (19%) cases, peaking at 22 weeks' gestation, with significantly more black mothers having ascending infection compared with other ethnicities (P < 0.0001). Maternal vascular malperfusion was the largest category of placental abnormalities in stillbirth, with peak prevalence in the early third trimester. There were 18 (2%) cases with specific histological abnormalities, including chronic histiocytic intervillositis and massive perivillous fibrin deposition.

CONCLUSIONS

Placental pathologies represent the largest category of cause of intrauterine death. Placental histological examination is the single most useful component of the autopsy process in this clinical setting. A minority of cases are associated with specific placental pathologies, often with high recurrence rates, that can be diagnosed only on microscopic examination of the placenta. Many deaths remain unexplained, although placental histological lesions may be present which are of uncertain significance. A rigorous, systematic approach to placental pathology research and classification may yield better understanding of the significance of placental findings and reduce the rate of unexplained intrauterine deaths. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Organ weights and ratios for postmortem identification of fetal growth restriction: utility and confounding factors

OBJECTIVES

The postmortem fetal brain:liver weight ratio is commonly used as a marker of nutrition for diagnosis of fetal growth restriction (FGR). However, there are limited data regarding the effects of intrauterine retention, fetal maceration and postmortem interval on organ weights and their ratios at autopsy. Our aims were to examine the relationships between gestational-age-adjusted and sex-adjusted fetal organ weights at autopsy, cause of intrauterine death and effects of intrauterine retention, and to determine whether the brain:liver weight ratio is a reliable marker of FGR in intrauterine death.

METHODS

As part of a larger study examining autopsy findings in intrauterine death, data from two specialist centers in London were collated in a specially designed database. Autopsy and clinical information for > 1000 intrauterine deaths between 2005 and 2013 were extracted. Adjusted (delta) organ weights were calculated by plotting against gestational age female and male brain, liver, thymus, heart, combined kidney, combined lung, spleen and combined adrenal gland weights. Polynomial regression was used to determine best fit and to calculate expected (50^th centile) organ weights and deviations from expected. We compared adjusted organ weights and body:organ weight ratios in fetuses which were small-for-gestational age (SGA) at autopsy (birth weight < 10^th centile for normal live births) vs those in fetuses which were not, and in macerated vs non-macerated fetuses.

RESULTS

The majority of fetal organs (brain, liver, heart, thymus, lungs, kidneys and thyroid) in SGA fetuses were significantly lighter than those in non-SGA fetuses. Body:organ weight ratios for thymus, liver and spleen were significantly greater in SGA fetuses, indicating these organs to be disproportionately small. The majority of organs were significantly lighter in macerated compared with non-macerated fetuses and body:organ weight ratios for most organs (liver, thymus, lung, pancreas, adrenal gland, kidney, heart) were significantly greater in macerated compared with non-macerated fetuses. When SGA cases with demonstrable placental histological abnormalities were compared with other SGA cases, there was a significant difference in the brain:liver weight ratio (median, 6 vs 3.5).

CONCLUSION

Changes after intrauterine death lead to loss of fetal weight, with preferential weight loss of visceral organs such as the liver. Maceration therefore affects the brain:liver weight ratio and adjustment should be made for such changes during interpretation of ratios. Fetal organ weights may be affected significantly by mechanism of death and postmortem changes. The fetal brain:liver weight ratio may provide useful information regarding intrauterine growth status at time of death, provided that adjustment is made for effects of intrauterine retention and that appropriate cut-off values are used. Copyright © 2016 ISUOG. Published by John Wiley & Sons Ltd.

Classification of stillbirths is an ongoing dilemma

AIM

To compare different classification systems in a cohort of stillbirths undergoing a comprehensive workup; to establish whether a particular classification system is most suitable and useful in determining cause of death, purporting the lowest percentage of unexplained death.

METHODS

Cases of stillbirth at gestational age 22-41 weeks occurring at the Department of Gynecology and Obstetrics of Foggia University during a 4 year period were collected. The World Health Organization (WHO) diagnosis of stillbirth was used. All the data collection was based on the recommendations of an Italian diagnostic workup for stillbirth. Two expert obstetricians reviewed all cases and classified causes according to five classification systems.

RESULTS

Relevant Condition at Death (ReCoDe) and Causes Of Death and Associated Conditions (CODAC) classification systems performed best in retaining information. The ReCoDe system provided the lowest rate of unexplained stillbirth (14%) compared to de Galan-Roosen (16%), CODAC (16%), Tulip (18%), Wigglesworth (62%).

CONCLUSION

Classification of stillbirth is influenced by the multiplicity of possible causes and factors related to fetal death. Fetal autopsy, placental histology and cytogenetic analysis are strongly recommended to have a complete diagnostic evaluation. Commonly employed classification systems performed differently in our experience, the most satisfactory being the ReCoDe. Given the rate of "unexplained" cases, none can be considered optimal and further efforts are necessary to work out a clinically useful system.

Post-mortem magnetic resonance foetal imaging: a study of morphological correlation with conventional autopsy and histopathological findings

The aim of the present study is to offer our experience concerning post-mortem magnetic resonance (PMMR) in foetal death cases and an evaluation of the differences between the findings acquired by PMMR and by forensic autopsy. Fifteen foetuses were recruited from July 2014 to December 2015. These had suffered intrauterine death in women in the 21st to 38th week of gestation who were treated in the emergency department for non-perception of foetal movements. We performed a PMMR on foetuses, 3 ± 1 days on average from the time of death, and then a complete forensic autopsy was performed. All 15 foetuses were examined with a whole-body study protocol, starting from the skull, down to and including the lower limbs. The total time of examination ranged from 20 to 30 min in each case. The external evaluation and description of post-mortem phenomena (maceration), record of the weight and detection and the various measurements of foetal diameters were evaluated before performing autopsy. A complete histopathological study was performed in each case. Out of 15 cases examined, eight were negative for structural anatomical abnormalities and/or diseases, both in the preliminary radiological examination and the traditional autopsy. In the remaining seven cases, pathological findings were detected by PMMR with corresponding results at autopsy. PMMR can provide useful information on foetal medical conditions and result in improved diagnostic classification. It may enable the planning of a more suitable technique before proceeding to autopsy, including focusing on certain aspects of organ pathology otherwise not detectable. The association between PMMR, post-mortem examination and related histological study of the foetus-placenta unit could help reduce the percentage of cases in which the cause of foetal death remains unexplained. Lastly, it may allow a selective sampling of the organ in order to target histological investigations.

Is the diagnostic yield influenced by the indication for fetal autopsy?

The utility of fetal autopsy to corroborate antenatal ultrasound findings and to aid genetic counseling is well known. However, the ability to identify an underlying cause for the common indications for which it is performed is not well studied. This study aimed to determine if the diagnostic yield of fetal autopsy in identifying the underlying cause is determined by the indication of the autopsy. Five groups of fetuses were defined based on the indication for the autopsy performed in 903 cases: (i) malformations, (ii) intrauterine death (IUD), (iii) cystic hygroma and hydrops fetalis, (iv) isolated abnormalities of amniotic fluid, and (v) intrauterine growth restriction (IUGR). The highest diagnostic yield was in fetuses with isolated abnormalities of amniotic fluid (77%), followed by those with IUGR (75%), with IUD (69.6%), those in group five (55.2%) and lowest (45%) in fetuses with malformations (P < 0.001). A cause was identified in 77.8% fetuses with multiple malformations compared to 37.5% with isolated malformations (P < 0.001), with chromosomal abnormalities in 31.8% versus 9.9% respectively (P < 0.001) and malformation syndromes in 42.5% versus 26.3% (P < 0.001). Placental examination provided the highest yield in IUD, IUGR, and oligohydramnios (43.1%; P < 0.003) whereas chromosomal analysis was most useful in cystic hygroma/NIHF (28.9%; P < 0.001). This information on the diagnostic yield in fetal autopsy related its common indications, can be utilized to counsel families of the utility of autopsy to establish cause and recurrence risks and thereby assist then to make an informed decision to consent for the procedure. © 2016 Wiley Periodicals, Inc.

Maternal plasma angiogenic index-1 (placental growth factor/soluble vascular endothelial growth factor receptor-1) is a biomarker for the burden of placental lesions consistent with uteroplacental underperfusion: a longitudinal case-cohort study

BACKGROUND

Placental lesions consistent with maternal vascular underperfusion (MVU) are thought to be pathogenically linked to preeclampsia, small-for-gestational-age newborns, fetal death, and spontaneous preterm labor and delivery; yet, these lesions cannot be diagnosed antenatally. We previously reported that patients with such conditions and lesions have an abnormal profile of the angiogenic placental growth factor (PlGF) and antiangiogenic factors (eg, soluble vascular endothelial growth factor receptor [sVEGFR]-1).

OBJECTIVE

The objectives of this study were to: (1) examine the relationship between the maternal plasma PlGF/sVEGFR-1 concentration ratio (referred to herein as angiogenic index-1) and the burden of histologic placental features consistent with MVU; and (2) test the hypothesis that angiogenic index-1 can identify patients in the midtrimester who are destined to deliver before 34 weeks of gestation with multiple (ie, ≥3) histologic placental features consistent with MVU.

STUDY DESIGN

A 2-stage case-cohort sampling strategy was used to select participants from among 4006 women with singleton gestations enrolled from 2006 through 2010 in a longitudinal study. Maternal plasma angiogenic index-1 ratios were determined using enzyme-linked immunosorbent assays. Placentas underwent histologic examination according to standardized protocols by experienced pediatric pathologists who were blinded to clinical diagnoses and pregnancy outcomes. The diagnosis of lesions consistent with MVU was made using criteria proposed by the Perinatal Section of the Society for Pediatric Pathology. Weighted analyses were performed to reflect the parent cohort; "n*" is used to reflect weighted frequencies.

RESULTS

(1) Angiogenic index-1 (PlGF/sVEGFR-1) concentration ratios were determined in 7560 plasma samples collected from 1499 study participants; (2) the prevalence of lesions consistent with MVU was 21% (n* = 833.9/3904) and 27% (n* = 11.4/42.7) of women with ≥3 MVU lesions delivered before 34 weeks of gestation; (3) a low angiogenic index-1 (<2.5th quantile for gestational age) in maternal plasma samples obtained within 48 hours of delivery had a sensitivity of 73% (n* = 8.3/11.4; 95% confidence interval [CI], 47-98%), a specificity of 94% (n* = 3130.9/3316.2; 95% CI, 94-95%), a positive likelihood ratio of 12.2, and a negative likelihood ratio of 0.29 in the identification of patients who delivered placentas with ≥3 MVU lesions at <34 weeks; (4) prospectively, at 20-23 weeks of gestation, a maternal plasma concentration of angiogenic index-1 <2.5th quantile identified 70% (n* = 7.2/10.3; 95% CI, 42-98%) of patients who delivered placentas with ≥3 MVU lesions before 34 weeks (specificity, 97% [n* = 2831.3/2918; 95% CI, 96-98%]; positive likelihood ratio, 23; negative likelihood ratio, 0.31); and (5) among women without obstetrical complications who delivered at term, angiogenic index-1 was lower in women with than without placental lesions consistent with MVU (P < .05).

CONCLUSION

Maternal plasma angiogenic index-1 (PlGF/sVEGFR-1) is the first biomarker for the burden of placental lesions consistent with MVU. We propose that an accumulation of these lesions in placentas delivered before 34 weeks is a histologic counterpart of an antiangiogenic profile.

Stillbirth: Correlations Between Brain Injury and Placental Pathology

Chronic placental pathologic processes such as fetal thrombotic vasculopathy have been linked to brain injury in neonates. We hypothesize that using stillbirth as a model, placental pathology can predict risk for hypoxic-ischemic brain injury. From a single institutional database of stillbirths ≥23 weeks' gestational age, we included cases with full autopsy and neuropathology examination. Bivariable analyses were performed to identify whether there was an association between placental pathologic findings and neuropathologic findings. Logistic regression was used to control for potential confounders. Among 97 potential cases, adequate tissue was analyzable from 79 cases (mean gestational age  =  33 weeks). Acute central nervous system hemorrhage and acute neuronal necrosis were the most common neuropathologic processes seen in this cohort (57% for each). Maternal vascular underperfusion was the most common placental pathology but was not significantly associated with a specific neuropathologic finding. High-grade chronic villitis (HGCV) and fetal thrombotic vasculopathy (FTV) were significantly associated with increased risk for pontosubicular necrosis (odds ratios, 15.73 and 3.79, respectively). These associations persisted after controlling for potential confounders. Chronic placental pathologies, specifically HGCV and FTV, were associated with pontosubicular necrosis, suggesting that placental pathology involving the fetal vasculature and altered fetoplacental blood flow carry the greatest likelihood of hypoxic/ischemic brain injury.

IFPA Gábor Than Award Lecture: Recognition of placental failure is key to saving babies' lives

In high-income countries, placental failure is implicated in up to 65% of cases of stillbirth. Placental failure describes the situation where the placenta cannot meet the fetus' needs and may be the end-result of a variety of underlying pathological processes evident in the placental disc, membranes and umbilical cord. These include lesions with genetic, environmental, infectious, inflammatory, mechanical, metabolic, traumatic or vascular origin. Investigation of placental tissue from stillbirths and from pregnancies at an increased risk of stillbirth has demonstrated changes in macroscopic and microscopic structure which are themselves related to abnormal placental function. A better understanding and identification of placental failure may improve the management of pregnancy complications and of pregnancies after stillbirth (which have a 5-fold increased risk of stillbirth). The majority of current antenatal tests focus on the fetus and its response to the intrauterine environment; few of these investigations reduce stillbirths in low-risk pregnancies. However, some currently used investigations reflect placental development, structure and vascular function, while other investigations employed in clinical research settings such as the evaluation of placental structure and shape have a good predictive value for adverse fetal outcome. In addition, recent studies suggest that biomarkers of placental inflammation and deteriorating placental function can be detected in maternal blood suggesting that holistic evaluation of placental structure and function is possible. We anticipate that development of reliable tests of placental structure and function, coupled to assessment of fetal wellbeing offer a new opportunity to identify pregnancies at risk of stillbirth and to direct novel therapeutic strategies to prevent it.

A pathologist׳s perspective on the perinatal autopsy

The perinatal autopsy is an important tool in the investigation of fetal and neonatal death, and a complete understanding of its risks and benefits is necessary for providers of perinatal care. This review, from the perspective of a perinatal pathologist, reports the details of the autopsy procedure, its goals, its value to individual patients and the health care system in general, and its alternatives. Even with new emerging technologies, the conventional perinatal autopsy remains the gold standard for determining the cause of death and the final summary of all pathologic findings. Therefore, the information provided in this review can help providers properly convey information about perinatal autopsy to bereaved families.

Foetal autopsy-categories and causes of death

INTRODUCTION

Intrauterine death(IUD)/ Stillbirth forms a major part of perinatal mortality which thereby is a good indicator of pregnancy wastage as well as quality of healthcare available. The key objectives of autopsy examination are to know the cause(s) of death, elucidation of pathogenic mechanism and quality control of clinical management. The aim of this study was to identify the prevalent causes of IUD, thereby taking appropriate measures to prevent them and decrease the perinatal mortality rate.

MATERIALS AND METHODS

The study included 14 cases of IUD received for autopsy in the Department of Pathology over a period of five years. Autopsies were performed as per standard protocol and included full anthropometric profile, external examination, gross and microscopic evaluation of different organs and placenta.

RESULTS

Total number of 14 fetal autopsies were performed over a period of 5 years. The causes were broadly classified as fetal, maternal and placental. Placental causes were seen in majority of cases (48.57%) followed by fetal (35.72%) and then maternal (21.42). Most prevalent cause of death was congenital anomalies (28.6%) followed by placental insufficiency (21.4%) and chorioamnionitis (14.2%).

CONCLUSION

Determination of causes of fetal death would prove beneficial to the clinicians and parents for better management and care in future pregnancies as well as in genetic counseling.

Placental pathology, perinatal death, neonatal outcome, and neurological development: a systematic review

BACKGROUND

The placenta plays a crucial role during pregnancy for growth and development of the fetus. Less than optimal placental performance may result in morbidity or even mortality of both mother and fetus. Awareness among pediatricians, however, of the benefit of placental findings for neonatal care, is limited.

OBJECTIVES

To provide a systematic overview of the relation between placental lesions and neonatal outcome.

DATA SOURCES

Pubmed database, reference lists of selected publications and important research groups in the field.

STUDY APPRAISAL AND SYNTHESIS METHODS

We systematically searched the Pubmed database for literature on the relation between placental lesions and fetal and neonatal mortality, neonatal morbidity and neurological outcome. We conducted three separate searches starting with a search for placental pathology and fetal and neonatal mortality, followed by placental pathology and neonatal morbidity, and finally placental pathology and neurological development. We limited our search to full-text articles published in English from January 1995 to October 2013. We refined our search results by selecting the appropriate articles from the ones found during the initial searches. The first selection was based on the title, the second on the abstract, and the third on the full article. The quality of the selected articles was determined by using the Newcastle-Ottawa Quality Assessment Scale.

RESULTS

Placental lesions are one of the main causes of fetal death, where placental lesions consistent with maternal vascular underperfusion are most important. Several neonatal problems are also associated with placental lesions, whereby ascending intrauterine infection (with a fetal component) and fetal thrombotic vasculopathy constitute the greatest problem.

CONCLUSIONS

The placenta plays a key role in fetal and neonatal mortality, morbidity, and outcome. Pediatricians should make an effort to obtain the results of placental examinations.

Fetal bacterial infections in antepartum stillbirth: a case series

OBJECTIVES

This study aims to assess the frequency of fetal bacterial infections in stillbirth (SB) and to evaluate the best samples for the diagnosis of infection-related SB.

STUDY DESIGN

Consecutive cases of antepartum SB were enrolled. Vaginal and placental swabs, as well as heart blood cultures and surface swabs from the neonate, were collected. Histological examinations were performed by the same examiner. Immunohistochemistry for leukocyte common antigen was performed in the placenta and fetus. Each case was discussed in a multidisciplinary audit.

RESULTS

One hundred and nine cases were enrolled. Fetal blood cultures were positive in 20/95 cases (21%). Significant histological findings in the placenta/cord and in at least one fetal organ were observed in 8 cases of them (4 Group B Streptococcus GBS, 2 Listeria monocytogenes, 1 Coagulase negative Staphylococcus, 1 Pseudomonas aeruginosa). Neither tissue damage nor inflammatory infiltrate was found in the 12 remnant cases. Funisitis while not histological chorioamnionitis was associated with microbiological findings. Positive findings in maternal/placental/fetal swabs occurred in 18-32% of cases with both negative fetal blood cultures and histopathological findings. With the exception of GBS, no other bacteria agent could be detected by any of the swabs.

CONCLUSIONS

Eight cases (8.4%) fulfilled both microbiological and histology criteria allowing the diagnosis of SB-related fetal infection demonstrating that search for infections is essential in SB evaluation. Fetal blood culture, placenta swab for GBS and search for histological funisitis are mandatory actions within the SB work-up in order to guide pathology examination and reach clinical conclusions.

Causes of stillbirth at different gestational ages in singleton pregnancies

OBJECTIVE

To compare causes of stillbirth in preterm and term pregnancies.

DESIGN

Cohort study.

SETTING

All delivery wards in Stockholm, 1998-2009.

POPULATION

Stillbirths from singleton pregnancies of gestational age ≥22(+0) (n = 1089) extracted from a web-based database including all stillbirths in the major Stockholm area since 1998.

METHODS

The parents of the stillborns were all offered an extensive standardized investigation. The causes of death were assigned in a perinatal audit using the Stockholm classification of stillbirth. Singleton stillbirths were divided into preterm (gestational week 22(+0) -36(+6) ) and term/post-term (gestational week ≥37(+0) ). The term/post-term group was subdivided into term (gestational week 37(+0) -40(+6) ) and post-term stillbirths (gestational week ≥41(+0) ).

MAIN OUTCOME MEASURE

Causes of stillbirth at different gestational ages.

RESULTS

A higher proportion of placental abruption and preeclampsia/hypertension was seen in preterm stillbirths compared with term/post-term stillbirths, which instead had a higher proportion of umbilical cord complications and infection. Infection was more common in post-term than term stillbirths (46.5 vs. 19.8%, p < 0.001).

CONCLUSION

Increased knowledge of causes of stillbirth in different gestational ages may be valuable in developing strategies for prevention of fetal death. The high proportion of infection in post-term stillbirths could be clinically important and warrants further studies.

[Evaluation of intrauterine death: importance of examination of fetal, placental and maternal factors]

AIMS

Intrauterine death is a multifactorial major complication during pregnancy. In this retrospective analysis the pathological anatomical findings of fetuses and placentas as well as maternal factors were evaluated.

MATERIAL AND METHODS

A retrospective screening of post-mortem examinations, corresponding placental examinations and clinical data on maternal status (1998-2008) was carried out. A classification of all findings was made with the ReCoDe system and induced abortions and cases with incomplete data were excluded from the study.

RESULTS

A total of 84 pregnancies involving 87 fetuses (9 siblings) were evaluated. The median gestation age was 20 weeks (range 12-41). The evaluation based on the ReCoDe system revealed that intrauterine death was mainly associated with placental diseases (n = 63) and to a lesser extent with fetal malformations (n = 15) or maternal diseases (n = 4). Idiopathic cases were rare (n = 2).

CONCLUSIONS

Placental examination is important for explaining intrauterine death because in most cases an association with placental diseases can be found but fetal malformation and maternal diseases must be taken into account.

Pathologic Examination of Fetal and Placental Tissue Obtained by Dilation and Evacuation

Context.—Dilation and evacuation (D&E) is an alternative method to induction of labor for pregnancy termination and intrauterine fetal demise, and it is the most common mode of second-trimester uterine evacuation in the United States. Many D&E specimens are examined in surgical pathology, and there is little information available in surgical pathology textbooks or the literature to assist pathologists in these examinations.

Objective.—To provide an overview of the D&E procedure, discuss related legal issues, provide guidelines for routine pathologic examination of D&E specimens, and demonstrate the importance of careful pathologic examination of D&E specimens.

Data Sources.—Case-derived material and literature review.

Conclusions.—Pathologic examination of D&E specimens has been understudied. However, the available literature and our experience support the fact that careful pathologic examination of D&E specimens can identify significant fetal and placental changes that can confirm clinical diagnoses or provide definitive diagnosis, assist in explaining the cause of intrauterine fetal demise, and identify unexpected anomalies that may provide further clues to a diagnostic syndrome or mechanism of anomaly formation.

Sharing experiences to improve bereavement support and clinical care after stillbirth: report of the 7th annual meeting of the International Stillbirth Alliance

Stillbirth remains a global health challenge which is greatly affected by social and economic inequality, particularly the availability and quality of maternity care. The International Stillbirth Alliance (ISA) exists to raise awareness of stillbirth and to promote global collaboration in the prevention of stillbirth and provision of appropriate care for parents whose baby is stillborn. The focus of this ISA conference was to share experiences to improve bereavement support and clinical care. These issues, relevant throughout the globe, are not discrete but closely interrelated, with both similarities and differences depending on the specific country and cultural context. Counting stillbirths and understanding the causes of stillbirth are essential not only for providing optimal care and support to parents whose babies die, but also for reducing the future burden of stillbirth. This summary highlights novel work from obstetricians, midwives, psychologists, parents and peer support organizations that was presented at the ISA meeting. It covers topics including the bereavement process, peer support for parents, support and training for staff, evidence for clinical care, and the need for accurate data on stillbirths and perinatal audits. Representatives from the maternity services of the region presented their outcome data and shared their experiences of clinical and bereavement care. Data and developments in practice within stillbirth and bereavement care must be widely disseminated and acted upon by those responsible for maternity care provision, both to prevent stillbirths and to provide high-quality care when they do occur.

Fetal central nervous system injury in third trimester stillbirth: a clinicopathologic study of 63 cases

We report the neuropathologic findings and clinicopathologic associations in 63 3rd trimester singleton stillborn fetuses. All were ≥ 28 weeks estimated gestational age (EGA) with complete autopsies, including placental examination. Fetuses with chromosomal abnormalities, major congenital anomalies, and intrapartum demise were excluded. The cases were divided into those with abruption (n  =  12) and those with unexplained fetal demise (n  =  51). The latter group was then subdivided by gestational age with 3 subgroups (preterm 28 to < 32 weeks EGA (n  =  16), preterm 32 to <37 weeks EGA (n  =  13), and term 37-41 weeks EGA (n  =  22). Each group was further subdivided as appropriate-for-gestational age/large-for-gestational age (AGA/LGA) or small-for-gestational age (SGA). Placental lesions were also evaluated and correlated with brain lesions. Established or recent injury involving gray or white matter was seen in 88% of the fetuses with unexplained demise versus 42% with abruption (P  =  0.001). The most common form of brain injury was established gray matter damage, seen in 65% of the fetuses with unexplained demise versus 25% with abruption (P  =  0.021), the most common pattern being established pontosubicular neuronal necrosis plus established neuronal necrosis in other sites. There was no significant difference in the frequency of brain injury between the SGA fetuses and AGA/LGA fetuses or between the unexplained stillbirth preterm and term subgroups, and there was no unequivocal correlation between placental lesions and brain lesions. Brain injury, most frequently established gray matter damage, is seen in the majority of stillborn infants with unexplained demise, indicating that the brain injury predates the period immediately before death.

Unexplained fetal death has a biological signature of maternal anti-fetal rejection: chronic chorioamnionitis and alloimmune anti-human leucocyte antigen antibodies

AIMS

Chronic chorioamnionitis is a histological manifestation of maternal anti-fetal cellular rejection. As failure of graft survival is the most catastrophic event in organ transplantation, we hypothesized that fetal death could be a consequence of maternal rejection. The aim of this study was to assess whether there is evidence of cellular and antibody-mediated rejection in fetal death.

METHODS AND RESULTS

Placental histology was reviewed for the presence of chronic chorioamnionitis in unexplained preterm fetal death (n=30) and preterm live birth (n=103). Amniotic fluid CXCL10 concentrations were measured with a specific immunoassay. Chronic chorioamnionitis was more frequent in fetal death than in live birth (60.0% versus 37.9%; P<0.05) and fetal death had a higher median amniotic fluid CXCL10 concentration than live birth (2.0 versus 1.8 ng/ml, P<0.05), after adjusting for gestational age at amniocentesis. Maternal anti-human leucocyte antigen class II panel-reactive seropositivity determined by flow cytometry was higher in fetal death compared to live birth (35.7% versus 10.9%; P<0.05).

CONCLUSIONS

Chronic chorioamnionitis is a common pathologic feature in unexplained preterm fetal death. This novel finding suggests that cellular and antibody-mediated anti-fetal rejection of the mother is associated with fetal death (graft failure) in human pregnancy.

Genome-wide array-based copy number profiling in human placentas from unexplained stillbirths

OBJECTIVE

Accumulating evidence suggests that genomic structural variations, particularly copy number variations (CNV), are a common occurrence in humans that may bear phenotypic consequences for living individuals possessing the variant. While precise estimates vary, large-scale karyotypic abnormalities are present in 6-12% of stillbirths (SB). However, due to inherent limitations of conventional cytogenetics, the contribution of genomic aberrations to stillbirth is likely underrepresented. High-resolution copy number variant analysis by genomic array-based profiling may overcome such limitations.

METHODS

Prospectively acquired SB cases > 22 weeks underwent classification of 'unexplained' stillbirth by Wigglesworth and Aberdeen criteria after extensive testing and rigorous multidisciplinary audit. Genome-wide analysis was conducted using high-resolution Illumina single nucleotide polymorphism (SNP) arrays (Human CNV370-Duo) on placental and fetal samples. Potential alternate detection methods were completed by one or more of three independent means (quantitative PCR, Illumina1M, or Agilent105K comparative genomic hybridization arrays).

RESULTS

In our cohort of 54 stillbirths, 29 met strict unexplained criteria. Among these, we identified 24 putative novel CNVs. Subsequent interrogation detected 18 of 24 CNVs (75%) in placental samples, 8 of which were also confirmed in available fetal samples; none were present in maternal blood.

CONCLUSION

We describe the potential of whole-genome placental profiling to identify small genomic imbalances, which might contribute to a small proportion of well-characterized, unexplained stillbirths.