If you've ever had your bed buddy tossing and turning next to you at 4am, you'll probably raise your eyebrows at the results of a new study out of Europe.
Sharing a bed with a partner could mean an increase in having a more restful night's sleep, according to researchers from the Centre for Integrative Psychiatry in Germany.
Investigating the relationship between bed-sharing and sleep quality, the researchers found that couples who slept together were better off.
Dr Henning Johannes Drews and his team conducted the study over four nights with 12 young, healthy, heterosexual couples. They measured the quality of sleep with and without a partner, using a technique called dual simultaneous polysomnography, which is an "exact, detailed and comprehensive method to capture sleep on many levels - from brain waves to movements, respiration, muscle tension, movements and heart activity".
The participants also completed questionnaires to better understand the couples' relationship characteristics.
The results showed that rapid-eye-movement (REM) sleep was both increased and less disrupted in couples sleeping together compared to when they slept individually.
REM sleep, which is associated with vivid dreams, has previously been linked to emotion regulation, memory consolidation, social interactions, and creative problem-solving.
The researchers also found that couples synchronise their sleep patterns when sleeping together, which is positively associated with a better relationship, and an increase in limb movement.
Dr Drews said that while the results are promising, further studies are required to better understand their findings.
"The first thing that is important to be assessed in the future is whether the partner-effects we found (promoted REM sleep during co-sleep) are also present in a more diverse sample (e.g., elderly, or if one partner suffers from a disease)," he added.