Sleeping posture from 28 weeks’ gestation to birth is important for all pregnancies regardless of risk factors1
A recent meta-analysis showed that, compared with the left-lateral going-to-sleep position, the supine going-to-sleep position was associated with stillbirth (adjusted odds ratio [OR] 2.63, 95% confidence interval [CI] 1.72–4.04).1 A secondary analysis of these data showed that, compared with a nonsupine going-to-sleep position, the supine going-to-sleep position was associated with giving birth to a small-for-gestational-age neonate (adjusted OR 3.23, 95% CI 1.37–7.59).2
Going-to-sleep posture at night and waking posture in the morning help determine whether pregnant patients spend a large proportion of time sleeping supine
If patients’ going-to-sleep posture is supine, on average, they will spend 50% of the night supine.3 If their waking posture in the morning is supine, on average, they have spent 33% of the night supine.3
Clinicians should advise all pregnant patients about sleeping posture4
Current evidence indicates that before 28 weeks’ gestation sleeping posture does not affect pregnancy outcomes.5 Starting at 28 weeks’ gestation, pregnant patients should be advised to avoid going to sleep supine4 and that going to sleep on the right side appears to be equally as safe as on the left.1,2
Modifying sleeping position using pillows may be helpful
A randomized trial that included 35 pregnancies greater than 28 weeks’ gestation and across 469 nights of observation indicated that pregnancy pillows and regular pillows were equally effective at reducing supine sleep in late pregnancy, with an average of 13%–16% of the night (roughly 1 hour) spent supine.6
Clinicians can also advise patients on positional-therapy or sleep-modification devices
Positional therapy is a safe and effective treatment from the field of sleep medicine. In 2 feasibility studies including 45 pregnant individuals across 90 nights in the third trimester, a positional-therapy device significantly reduced the time spent in the supine position.7,8 In a randomized trial with 181 participants, the same device did not have a significant effect on birth weight or birth-weight centile compared with a sham device.9
Footnotes
Competing interests: Allan Kember is listed as an inventor on a patented maternity belt (PrenaBelt) for use during sleep in pregnancy. Dr. Kember is president, CEO, and majority shareholder of Shiphrah Biomedical, which is a research-based medical device company specializing in sleep during pregnancy. No other competing interests were declared.
This article has been peer reviewed.
References
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