Partner disturbance in co-sleeping and effects on sleep architecture: A systematic review

This systematic review summarizes literature relating to 3 questions of interest: (RQ1) Is partner disturbance a common phenomenon in the sleep of healthy populations? (RQ2) What is the effect of co-sleeping on sleep architecture? (RQ3) What factors moderate the effect of co-sleeping on sleep architecture? Google scholar, Scopus, NCBI, Web of Science, Cochrane Library, and PsychInfo were searched on 7 September 2025, for articles relating to each research question. Risk of bias was assessed by first author using NOS-xs tool (Carra et al., 2025). Results relating to movement concordance, sleep architecture, and continuity metrics are reported, including percentage increase across groups. All 4 studies relating to RQ1 find evidence of partner disturbance. Two of 3 studies relating to RQ2 found increased REM duration in co-sleep compared to individual sleep. Eleven studies relating to RQ3 explored factors influencing sleep architecture in co-sleep, including presence of partner with sleep disordered breathing (SDB), insomnia, and interpersonal social factors. Overall, limitations of RQ1 studies include inconsistency in actigraphy measurement, including device used, sensitivity, and activity threshold algorithm and epoch length, as well as lack of control or measurement of disturbances outside of the couple. RQ2 was hampered by a small sample size investigating differences in sleep architecture between co-sleep and alone sleep, and lack of measurement of mediating factors. In RQ3, heterogeneity in studies and design protocol hamper interpretation of findings. This review summarizes literature relating to co-sleep effects on sleep architecture and finds that no single mechanism entirely explains net effects on sleep architecture.