Sleep Position and Baby Movements in Pregnancy
If your baby is moving less than usual, call your maternity unit now, whatever position you are lying in. The NHS advises going to sleep on your side, left or right, and Tommy's and Australia's Safer Baby programme say to do so from 28 weeks, because going to sleep on your back has been linked with a higher risk of stillbirth. The RCOG says there is some evidence that women feel most baby movements lying down, but not on their back.
Written by the Bumpi Kicks team at Speed AI Labs LLP. Last updated . General information, not reviewed by a clinician, and not medical advice. How we write and check these pages.
If your baby is moving less, contact your maternity unit now
Call your midwife or maternity unit immediately if your baby is moving less than usual, you cannot feel movement, or the usual pattern changes. Do not change position and wait to see if it helps. Do not wait until the next day.
If you cannot reach them, or you are worried about your own health, call your local emergency number.
What the sources say
Go to sleep on your side from 28 weeks
The NHS advises going to sleep on your side, left or right. Tommy's and Safer Baby give the same advice from 28 weeks, for daytime naps as well as at night.
Left or right: either side
Pooling five studies, Cronin and colleagues found going to sleep on the right side had similar odds to the left (aOR 1.04) and concluded both sides appear equally safe. Tommy's says one smaller study found the left side safer, that later studies have not found this, and that the left has not conclusively been shown to lower the risk compared with the right.
Waking on your back is not a problem
The NHS says not to worry if you wake on your back, Safer Baby says that is OK, and Tommy's says to settle back to sleep on your side. Tommy's says the research looked at the position you go to sleep in, and that this is the position you spend longest in.
How big the link is
The UK MiNESS study of 291 late stillbirths found going to sleep on the back was linked with 2.3 times the risk, compared with the left side. Pooling 851 stillbirths, Cronin and colleagues found 2.6 times. The NHS says research suggests it can double the risk after 28 weeks.
What the studies cannot show
These are case-control studies, in which women reported their sleep position. The MiNESS authors say more work is needed to show that changing position lowers stillbirth, while Cronin and colleagues call going to sleep on the back a contributing factor. Tommy's calls the research very reliable and says researchers do not know for certain what causes the higher risk.
Where you feel movements
The RCOG's 2026 guideline says there is some evidence that women feel most fetal movements when lying down, except on their back, fewer when sitting and fewest when standing. It does not discuss sleep position and stillbirth.
Why your baby may be quieter when you lie on your back
Tommy's says babies are less active when the mother lies on her back in late pregnancy. In a 2017 study of 29 healthy pregnancies, babies were more often in quiet sleep when the mother lay on her back than on her left side, and more often on her right side than her left.
What each source says about going-to-sleep position
| Source | What it says | Figure it gives |
|---|---|---|
| NHS | Go to sleep on your side, left or right; turn over if you wake on your back | Research suggests going to sleep on your back after 28 weeks can double the risk of stillbirth |
| Tommy's (reviewed June 2026) | Side from 28 weeks, naps included; left has not conclusively been shown safer than right | 2.6 times the risk when going to sleep on your back |
| Safer Baby (Australia) | Side from 28 weeks, either side; waking on your back is OK | Going to sleep on your side from 28 weeks can halve the risk, compared with going to sleep on your back |
| MiNESS study, UK, 2018 | 291 stillbirths compared with 733 ongoing pregnancies | aOR 2.31 for the back, compared with the left side |
| Cronin and colleagues, 2019 | Five case-control studies pooled: 851 stillbirths and 2,257 controls | aOR 2.63 for the back; right side 1.04 compared with the left |
| RCOG, 2026 | Some evidence that most movements are felt lying down, except on the back | No figure on sleep position |
Common questions
Does sleeping on your back cause stillbirth?
Studies have linked going to sleep on your back after 28 weeks with a higher risk, about 2.3 to 2.6 times in the two analyses we read, but they are case-control studies and cannot prove cause. The NHS advises going to sleep on your side, and Tommy's and Safer Baby say to do so from 28 weeks.
Is it better to sleep on your left side than your right?
Either side. Pooling five studies, Cronin and colleagues found the right side had similar odds to the left (aOR 1.04), and the NHS, Tommy's and Safer Baby all say left or right is fine.
What if I wake up on my back?
Turn onto your side and go back to sleep. The NHS says not to worry and Safer Baby says it is OK. Tommy's says the research looked at the position you go to sleep in.
Why does my baby move less when I lie on my back?
Tommy's says babies are less active when the mother lies on her back in late pregnancy, and the RCOG says there is some evidence that women feel most movements lying down but not on their back. If your baby is moving less than usual, call your maternity unit now rather than changing position and waiting.
Which position helps when counting kicks?
The RCOG says there is some evidence that women feel most movements lying down, except on their back. Cleveland Clinic suggests lying on your left side or sitting with your feet propped up while you count.
Does the advice apply to naps?
Yes. Tommy's and Safer Baby say to go to sleep on your side for daytime naps as well as at night, from 28 weeks.
Sources
These are the sources behind the statements on this page. We opened each one and checked it on the date shown.
- NHS, Tiredness and sleep problems in pregnancy, page last reviewed 11 March 2024
The NHS advises going to sleep on your side, left or right, and says research suggests that after 28 weeks falling asleep on your back can double the risk of stillbirth.
Limits: It says this may be to do with the flow of blood and oxygen to the baby, and not to worry if you wake on your back: turn over and go back to sleep on your side. The NHS page on preventing stillbirth (last reviewed 24 April 2024) gives the same advice without a number.
Checked . Read directly from the source.
- Tommy's, Sleep position in pregnancy Q&A, last reviewed 11 June 2026
Tommy's says going to sleep on your back after 28 weeks is linked with a 2.6 times higher risk of stillbirth, and that the left side has not conclusively been shown safer than the right.
Limits: It says the research is about the position you go to sleep in, which is the one you spend longest in, so if you wake on your back you can settle back to sleep on your side; that the advice covers naps; that babies are less active when the mother lies on her back; and that researchers do not know for certain what causes the higher risk. It calls the studies trials, but they are case-control studies. Read in a browser, because the page answers scripts with 403.
Checked . Read directly from the source.
- Safer Baby (Centre of Research Excellence in Stillbirth), Sleep on your side, no date shown
Australia's Safer Baby programme says to go to sleep on your side, either left or right, from 28 weeks, for naps and at night, and that waking on your back is OK.
Limits: It says going to sleep on your side from 28 weeks can halve the risk of stillbirth, compared with going to sleep on your back, and that lying on your back presses on major blood vessels and can reduce blood flow to the uterus.
Checked . Read directly from the source.
- Heazell A, Li M, Budd J, et al. Association between maternal sleep practices and late stillbirth: findings from a stillbirth case-control study (MiNESS). BJOG 2018
In a UK case-control study of 291 late stillbirths and 733 ongoing pregnancies, going to sleep on the back was linked with 2.3 times the risk of stillbirth, compared with the left side.
Limits: Read from the abstract. A case-control study in 41 UK maternity units from 28 weeks: it shows an association, positions were reported by the women, and the authors say further work is needed to find out whether changing position lowers stillbirth. It estimated that 3.7% of late stillbirths could be linked to going to sleep on the back.
Checked . Read directly from the source.
- Cronin RS, Li M, Thompson JMD, et al. An individual participant data meta-analysis of maternal going-to-sleep position, interactions with fetal vulnerability, and the risk of late stillbirth. EClinicalMedicine 2019;10:49-57
Pooling 851 late stillbirths and 2,257 controls, going to sleep on the back was linked with 2.6 times the risk; going to sleep on the right side had similar odds to the left.
Limits: Read from the abstract. It pooled five case-control studies of single pregnancies from 28 weeks without a major anomaly. The authors conclude that going to sleep on the left or right side appears equally safe. The data are observational, so the link is not proof that the position causes stillbirth.
Checked . Read directly from the source.
- Whitworth M, Fisher M, Heazell A, Royal College of Obstetricians and Gynaecologists. Reduced Fetal Movements, Green-top Guideline No. 57, second edition. BJOG 2026;133(8):e70-e92, first published 27 April 2026 (section 5)
The RCOG's 2026 guideline says there is some evidence women feel most fetal movements lying down, except on their back, fewer sitting and fewest standing (level 2+).
Limits: The same section says activity appears greatest in the evening. The guideline does not discuss going-to-sleep position or stillbirth, and gives no advice on the left or the right side.
Checked . Read directly from the source.
- Stone PR, Burgess W, McIntyre JPR, et al. Effect of maternal position on fetal behavioural state and heart rate variability in healthy late gestation pregnancy. Journal of Physiology 2017
In 29 healthy late pregnancies, babies were more often in quiet sleep when the mother lay on her back than on her left side, in a 2017 study of fetal heart rate patterns.
Limits: Read from the abstract. It measured the baby's state from its heart rate, not what the mothers felt, in a small group lying in set positions. Quiet sleep was also more likely on the right side than on the left.
Checked . Read directly from the source.
- Cleveland Clinic, Kick Counts (Fetal Movement Counting): Purpose & How To, page last updated 05/08/2026
Cleveland Clinic says a good time to feel movement may be when you sit down for a meal, and suggests lying on your left side or sitting with your feet propped up while you count.
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- NHS, Your baby's movements, page last reviewed 8 July 2024
The NHS says to call your midwife or maternity unit immediately if your baby moves less than usual, you cannot feel movement, or the usual pattern changes, and not to wait until the next day.
Limits: NHS advice is written for the UK. Advice elsewhere differs, and your own midwife or doctor comes first.
Checked . Read directly from the source.