Improving perinatal post-mortem data collection for stillborn babies

Background

A post-mortem is the medical examination that helps us understand what has happened when someone dies. For a baby, the post-mortem should be carried out by a pathologist with specialist knowledge and experience of carrying out post-mortems on babies.

All parents should be offered a post-mortem by senior staff at the hospital soon after their baby is stillborn. But fewer than half of all bereaved parents agree (consent) to this investigation. Parents find the decision extremely difficult for many reasons, and may think they won’t find out anything new about their baby’s death.

Although pathologists follow professional guidelines for post-mortems on babies, there is no agreed system for recording the information. The way that pathologists report their findings varies, so it is hard to compare reports from different pathology departments. The inconsistencies also make it hard to use post mortem information in research.
 

What did the project try to achieve?

This study involved developing a database using information from more than 1000 previously performed post-mortems (all unidentifiable). The information was reviewed, categorised and recorded in a useful way so that it could be compared.

The aim was to provide better understanding of which investigations are useful in helping us understand why babies die, and what research is likely to give us the most helpful information in the future. The study also resulted in a database that could help pathologists compare information from post-mortems in future research studies.
 

Results

1,065 post mortems have been reviewed. For each baby, the clinical information and post mortem findings have been put onto a specially designed research database. This has allowed the researchers to identify some patterns and also to see which investigations are the most helpful. Overall, a definite cause of death has been established for 393 babies, and 296 deaths remain entirely unexplained, with no apparent cause. Some abnormality was seen in 376 deaths; the abnormalities were mostly affecting the placenta, but it wasn’t clear how the baby had been affected.
 

What’s the most useful source of information in a post mortem?

Researchers found that when a cause could be found for the baby’s death, this could be done by studying the placenta, the clinical notes and looking at the baby’s organs. Taking samples of normal-looking organs to look at them under a microscope did not add useful additional information in most cases.

The study also tells us that, with our current knowledge, a definite or highly likely cause of death can be found for only around 4 in 10 babies who die. So the study highlights how much more work there is to do to find the causes underlying stillbirth and late miscarriage.
 

What does this study tell us about the placenta?

We know that problems affecting the placenta are responsible for a large proportion of deaths before birth. Yet very little is known about how the placenta works and what can go wrong. And we can’t test how well the placenta is working till quite late on in pregnancy. In this study, around one-third of the stillborn babies had signs of placental abnormalities, but it was not clear for all the babies whether this actually led to the death. If we are to unravel the tragedy of why babies die during pregnancy and achieve the government’s ambition to halve stillbirths by 2030, much more research is needed on the placenta. We need good-quality tests to check the placenta is working properly during pregnancy and to increase our understanding of how the placenta can malfunction.
 

The study seems to show that growth restriction in babies isn’t as common as was thought

During pregnancy, a baby’s growth will slow down (called ‘growth restriction’) if the placenta isn’t able to deliver enough nutrients and oxygen. This study provides new information about how pathologists should take into account the interval between the baby’s death in the womb and delivery, and also the time between delivery and post mortem. Although it’s likely that the number of babies with growth restriction has been overestimated up till now, it’s important to remember that around one-quarter of stillborn babies are growth-restricted even when all the intervals that will lead to weight loss are taken into account.
 

Impact of the research

The research has informed further work at Great Ormond Street Hospital for Children and University College London, also supported by Sands, developing less invasive methods of post-mortem examination. The research has also had an impact on NHS England policy and future plans for perinatal pathology nationally which aims to give all parents clear choices around post-mortem while also ensuring that the information produced by the post-mortem fits into an acceptable timescale for parents, especially in cases where a full post-mortem is unlikely to provide any more information than a less invasive one, as highlighted by this study.   

Who did the research?

The Principal Investigator on the project was Professor Neil Sebire, Great Ormond Street Hospital & Institute of Child Health UCL London, Professor of Paediatric Pathology. He worked with:

• Dr J Pryce, Clinical Research Associate in Paediatric Pathology GOSH/ICH
• Dr S Levine, Consultant in Paediatric Pathology St George’s Hospital, London
• Dr F Jessop, Consultant in Paediatric Pathology and Addenbrookes Hospital, Cambridge
• Prof G Smith, Professor of Obstetrics, Cambridge

The work took place at Department of Histopathology, Great Ormond Street Hospital and Institute of Child Heath.
 

Timings

This was a 2-year project running from 2013 to 2015. First results were presented at the Fetal Growth conference in 2015, with full publication in Ultrasound in Obstetrics and Gynecology in October 2016.
 

Funding from Sands

£100,000
 

Published papers

1. Man J, Hutchinson JC, Heazell AE, Ashworth M, Levine S and Sebire N J (2016), Stillbirth and intrauterine fetal death: factors affecting determination of cause of death at autopsy Ultrasound Obstet Gynecol 48: 566–573. doi:10.1002/uog.16016

2. Man J, Hutchinson J C, Ashworth M, Heazell A E, Jeffrey I and Sebire N J (2016) Stillbirth and intrauterine fetal death: contemporary demographic features of >1000 cases from an urban population Ultrasound Obstet Gynecol 48: 591–595. doi:10.1002/uog.16021

3. Man J, Hutchinson J C, Ashworth M, Judge-Kronis L, Levine S and Sebire N J (2016) Stillbirth and intrauterine fetal death: role of routine histological organ sampling to determine cause of death Ultrasound Obstet Gynecol 48: 596–601. doi:10.1002/uog.16020

4. Man J, Hutchinson J C, Ashworth M, Heazell A E, Levine S and Sebire N J (2016) Effects of intrauterine retention and postmortem interval on body weight following intrauterine death: implications for assessment of fetal growth restriction at autopsy Ultrasound Obstet Gynecol 48: 574–578. doi:10.1002/uog.16018

5. Man J, Hutchinson J C, Heazell A E, Ashworth M, Jeffrey I and Sebire N J (2016) Stillbirth and intrauterine fetal death: role of routine histopathological placental findings to determine cause of death Ultrasound Obstet Gynecol 48: 579–584. doi:10.1002/uog.16019

6. Man J, Hutchinson J C, Ashworth M, Jeffrey I, Heazell A E and Sebire N J (2016) Organ weights and ratios for postmortem identification of fetal growth restriction: utility and confounding factors Ultrasound Obstet Gynecol 48: 585–590. doi:10.1002/uog.16017