In 2011 a research trial in New Zealand [i] made links between the risk of stillbirth and babies’ movements, and other factors in pregnancy including, smoking, detection of small babies and the mother’s sleep position. Some of these factors were already known, but some were not. Sleep position in pregnancy was not previously considered to be a risk factor for stillbirth.
As both of these research trials were small, it was recommended that further research be carried out to test the hypothesis and the Midlands and North of England Stillbirth Study (MiNESS) was established to take this forwards, funded by Cure Kids (a New Zealand charity), Action Medical Research, Tommy's and Sands. At the same time, a similarily sized multicentre trial was also funded in New Zealand, also by Cure Kids.
In the MiNESS study, 400 women who had a stillbirth at or after 28 weeks gestation will complete a detailed questionnaire and talk to a research midwife about their sleeping habits and other aspects of their pregnancy. They will not be told the purpose of the study.
The information obtained from these questionnaires and conversations will be compared with those of a group of women who had healthy babies to see if there are any significant differences in their habits or experiences.
This study began in July 2014 and was initially going to be concluded in December 2015. Having received interest from a number of maternity units, however, the researchers applied for extra funding to extend the study by six months. This has meant the size of the study has increased which makes the results more reliable.
The MiNESS trial is now complete and the results are due to be published in August 2017.
The results of the New Zealand multi-centre trial [iii] mentioned above have now been published, and it has shown a four-fold increased risk in going to sleep supine (on your back) in late pregnancy. Researchers have called for a public-facing campaign letting women know that going to sleep on your side is safer.
The lead researcher of this study is Tommy’s Professor Alex Heazell.
The other researchers working on this project from the UK are Dr Tomasina Stacey at Dewsbury Hospital, Yorkshire, Dr Bill Martin at Birmingham Women’s Hospital and Dr Devender Roberts at Liverpool Women’s Hospital.
Professor Ed Mitchell and Professor Lesley McCowan at the University of Auckland, New Zealand, carried out the original research in New Zealand alongside Dr Stacey. They are also making up part of the research team.Hide details
This research is being conducted Tommy’s Stillbirth Research Centre in Manchester St Mary’s Hospital and lead by our Clinical Director Professor Alex Heazell.
The study had been funded through a partnership between Action Medical Research, Cure Kids and Sands.
Read more about position going to sleep in pregnancy here.Hide details
[i] Stacey T1, Thompson JM, Mitchell EA, Ekeroma AJ, Zuccollo JM, McCowan LM. Association between maternal sleep practices and risk of late stillbirth: a case-control study. BMJ. 2011 Jun 14;342:d3403. doi: 10.1136/bmj.d3403.
[ii] Gordon A1, Raynes-Greenow C, Bond D, Morris J, Rawlinson W, Jeffery H. Sleep position, fetal growth restriction, and late-pregnancy stillbirth: the Sydney stillbirth study. Obstet Gynecol. 2015 Feb;125(2):347-55. doi: 10.1097/AOG.0000000000000627.
[iii] Lesley ME, McCowan LME, Thompson JMD, Cronin RS et al (2017) Going to sleep in the supine position is a modifiable risk factor for late pregnancy stillbirth; Findings from the New Zealand multicentre stillbirth case-control study. PLOS One https://doi.org/10.1371/journal.pone.0179396