A new study has found a link between couples' sleep quality and the quality of their relationship.
It has shown that couples' relationship quality affects their sleep, and their sleep also affects their subsequent relationship functioning.
"When we look at the data on a day-by-day basis, there seems to be a vicious cycle in which sleep affects next day relationship functioning, and relationship functioning affects the subsequent night's sleep," said principal investigator Brant Hasler, clinical psychology doctoral candidate at the University of Arizona.
"In this cycle, conflict with one's partner during the day leads to worse sleep that night, which leads to more conflict the following day. Although these results are preliminary due to the relatively small sample size and a subjective measure of sleep quality, the woman's perception of the relationship seems particularly important, as it impacts both her own and her partner's subjective sleep quality that night," Hasler added.
The study involved data from 29 heterosexual, co-sleeping couples who did not have children. Each completed sleep diaries for seven days. Each partner was asked to record the quality of interactions with their partner six times a day.
The study showed that for men, better sleep was associated with more positive ratings of relationship quality the next day.
For women, negative partner interactions during the day were associated with poorer sleep efficiency for both themselves and their partner that night.
The study was presented at SLEEP 2009, the 23rd Annual Meeting of the Associated Professional Sleep Societies.