A new study suggests that couples are more likely to sleep in sync when the wife is more satisfied with their marriage.

Results show that overall synchrony in sleep-wake schedules among couples was high, as those who slept in the same bed were awake or asleep at the same time about 75 percent of the time. When the wife reported higher marital satisfaction, the percent of time the couple was awake or asleep at the same time was greater.

"Most of what is known about sleep comes from studying it at the individual level; however, for most adults, sleep is a shared behavior between bed partners," said lead author Heather Gunn, PhD, postdoctoral scholar at the University of Pittsburgh. "How couples sleep together may influence and be influenced by their relationship functioning."

The research abstract was published recently in an online supplement of the journal Sleep and was presented in Minneapolis, Minnesota, at SLEEP 2014, the 28th annual meeting of the Associated Professional Sleep Societies LLC.

The study group comprised 46 couples who completed relationship assessments. Objective sleep data also were gathered by actigraphy over a 10-day period.

"The sleep of married couples is more in sync on a minute-by-minute basis than the sleep of random individuals," said Gunn. "This suggests that our sleep patterns are regulated not only by when we sleep, but also by with whom we sleep."