A trial of a position modification device for the prevention of supine sleep during pregnancy

Background Self-reported going-to-sleep on the back during late pregnancy is related to an increase in stillbirth risk, possibly due to the enlarged uterus compressing major blood vessels supplying the placenta. This study aimed to test the effectiveness of a pillow designed to decrease supine sleep in pregnant women. Methods Thirty-five women in the third trimester of pregnancy used their own pillows for a control week and the intervention pillow for a week, in randomised order. Sleep position and total sleep time for each night of both weeks was monitored with the Night Shift Sleep Positioner, with a sleep study (WatchPat300) on the last night of each week to measure the impact of the intervention on sleep-disordered breathing. Results There was no difference in sleep time spent on the back overnight between the control or intervention pillow week, and hence no difference in the severity of sleep-disordered breathing across conditions. However, an increased percentage of back-sleeping overnight was significantly related to a higher degree of sleep-disordered breathing. Total sleep time was significantly longer while using the intervention pillow. Conclusion We found that the adoption of a pillow designed to discourage back sleeping was not effective in late pregnancy. Considering the reasonably high amount of back sleeping in our participants, alternative devices should be investigated.