Partner disturbance in co-sleeping and effects on sleep architecture: A systematic review.
Level 3 - non-randomized controlled study
Systematic review of predominantly non-randomized observational and cohort studies
PubMed 41720659 · doi:10.1016/j.sleh.2026.01.003
What was done
A systematic review was conducted across Google Scholar, Scopus, NCBI, Web of Science, Cochrane Library, and PsychInfo on September 7, 2025, to evaluate partner disturbance in healthy populations (RQ1), the effect of co-sleeping versus sleeping alone on sleep architecture (RQ2), and moderating factors (RQ3). Risk of bias was assessed using the NOS-xs tool.
What was found
All 4 studies addressing RQ1 found evidence of partner disturbance. For RQ2, 2 of 3 studies found increased REM duration during co-sleeping compared to sleeping alone. Eleven studies addressing RQ3 identified moderating factors, including partner sleep-disordered breathing, insomnia, and interpersonal social factors. The abstract reports directional findings but provides no specific numerical values or effect sizes.
Why it matters
This review synthesizes evidence on how bed-sharing influences sleep stages and movement disturbance, suggesting co-sleeping may alter REM sleep while being shaped by relationship factors and partner sleep disorders.
Limits
The evidence base is very small (only 3 studies evaluated sleep architecture differences). Studies were limited by inconsistent actigraphy algorithms and epoch lengths, failure to control for disruptions outside the couple, lack of mediator measurement, and substantial methodological heterogeneity.