Cot death may be influenced by where infants sleep

New research into cot death shows differences in the dead children’s brain tissue, depending on whether they slept in their own bed or together with their parents. Nevertheless, there is no justification for changing the recommendations for the prevention of cot death.

[Translate to English:] læge Lisbeth Lund Jensen forsvarer sit ph.d.-projekt om vuggedød den 14. november 2013.
[Translate to English:] læge Lisbeth Lund Jensen forsvarer sit ph.d.-projekt om vuggedød den 14. november 2013.

A PhD project from the Department of Forensic Medicine at Aarhus University now provides new knowledge for research in unexplained cot deaths. The study is based on brain tissue samples taken from Danish and Australian children who suffered cot death and it show changes in the brains. In particular the study shows that these changes were more pronounced among infants who died in their own bed, compared to children who suffered cot death while sleeping in the same bed as their parents. However, the results will not change the recommendations made by the Danish Health and Medicines Authority regarding where infants should sleep, explains Medical Doctor Lisbeth Lund Jensen, who is responsible for the PhD project:

”Unfortunately we have not yet cracked the code as to why some infants suddenly die in their sleep. But we have moved a step closer by being able to divide infants who suffer cot death into different groups. This will provide a more reliable basis for future research,” says Lisbeth Lund Jensen.

New groupings come as a surprise

Together with Australian researchers, she has studied tissue samples from the brains of 76 Danish and 48 Australian infants who all suffered cot death. That is to say that they died suddenly and unexpectedly during sleep.

Lisbeth Lund Jensen and her Australian colleagues succeeded in detecting a particular substance, which is seen in connection with oxygen deficiency in the brain. The researchers have also discovered a difference in the levels of the substance, depending on where the children had slept: “Children who slept alone had a higher level of the substance when compared to children who shared a bed with one or more adults. The research project also shows a different gender representation in the two groups of children. There were more boys in the group of children who slept alone, while there were the same number of boys and girls in the group that slept together with an adult.

The fact that more boys than girls suffer cot death is well-established by research. But that this over-representation is not seen in the group who sleep together with their parents is new knowledge. When seen together with the small differences in the brains, it is now possible to divide the group of children who suffer cot death into two well-defined sub-groups. This can contribute to a new understanding of the otherwise extremely complex concept of cot death," says Lisbeth Lund Jensen.

The results of the PhD project will now be included in the further research that is taking place in the area.


Lisbeth Lund Jensen defends her PhD project on 14 November, 2013. The title of the project is: ‘Beta-amyloid precursor protein - white matter changes in victims of sudden infant and early childhood death’.

The research is supported by:

  • The Australian SIDS and KIDS foundation
  • P. Carl Petersen's Foundation
  • Aase and Ejnar Danielsen’s Foundation
  • The Beckett Foundation
  • The King Christian X Foundation

Lisbeth Lund Jensen received the Australian Alice Davey Award research award in 2008 for her research. The award was established by parents who lost their daughter Alice to cot death in 1994.

Further information

Medical Doctor, PhD student Lisbeth Lund Jensen
Aarhus University, Department of Forensic Medicine
Mobile: +45 2993 7775