Bereaved parents who do not want to see their dead babies go through a conventional autopsy could in future be offered a less invasive option which uses magnetic resonance imaging and blood tests to establish the cause of death.
Scientists who investigated using a combination of full body scans and sample tests found this so-called minimally invasive autopsy (MIA) was as effective in determining the cause of death as a conventional procedure, which involves an open dissection of the baby's body to examine the organs.
"In a state of shock and grief, parents are asked if they will consent, and while they desperately want answers about why their baby died, many simply cannot contemplate what a postmortem entails."
Since the vast majority of parents whose babies die during or soon after birth currently refuse any autopsy, the researchers suggested the MIA could both improve rates of uptake and reduce parents' distress while offering clear answers.
"Autopsies not only help us to establish the cause of death, but they often play an important role in advancing medical research and knowledge," said Andrew Taylor, a consultant radiologist at London's Great Ormond Street Hospital and University College Hospital who co-led the study. "If we can find ways to continue to carry them out using less invasive methods, such as post-mortem MRI, we can boost our understanding of the many ways in which the body can go wrong."
In a study published in the journal the Lancet, Taylor and colleague Sudhin Thayyil, a consultant neonatologist, compared the accuracy of a standard autopsy with that of whole-body, post-mortem MRI with or without other minimally invasive tests. These included blood samples taken by needle, visual examination of the body, and genetic and metabolic tests.
The study involved 400 foetuses, babies, and children under 16 years old.
For foetuses and babies younger than a year, the MIA identified the same cause of death as the full autopsy for 92 percent of the cases studied, while in children aged one to 16, the MIA techniques were less accurate, with 54 percent of the two types of autopsies agreeing on cause of death.
The researchers said the difference in accuracy was probably because MRI was good at picking up abnormalities in organ structure or function, which are more likely to be causes of death in young babies, but unable to detect infections, which are more likely to be a cause of death in older children.
Experts say that currently in Britain, some 80 percent of parents whose baby dies shortly after birth refuse consent for a postmortem. This is despite evidence that autopsies find new and useful information in the majority of cases.
In the United States, Thayyil said, rates of autopsy in babies are even lower.
"In a state of shock and grief, parents are asked if they will consent, and while they desperately want answers about why their baby died, many simply cannot contemplate what a postmortem entails," said Charlotte Bevan of Sands, a charity that campaigns for more research into stillbirth and neonatal death. "Giving parents the option to have a less invasive but equally informative investigation will not only make the decision easier ... but could lead to an increase in postmortem up-take and vastly improved research into why so many babies are stillborn or die shortly after birth."