Not Surprisingly, Sleep Affects Your Relationship —Here's How

By Dr. Amy Muise
How did you sleep last night? Did you wake up this morning feeling refreshed and energized, or were you fatigued and sluggish? Your answers to these questions may provide some insight into how you'll interact with your significant other today.

In research conducted by Amie Gordon and Serena Chen from University of California, Berkeley, to be published in Social Psychological and Personality Science, participants completed a brief online survey each day for two weeks. Participants reported how long they slept, how many times they woke up during the night, how alert they felt upon waking, how tired they felt during the day, and whether they experienced any relationship conflicts.

Over the two-week study, people who slept worse on average reported more day-to-day conflict with their partners. But, even one poor night of sleep had an impact on relationship conflict. When people slept worse than they typically did, they were more likely to argue with their partners the next day. Although stress, anxiety, and conflict the previous day did impact a person’s sleep quality, the researchers were able to rule this out as a possible explanation for the findings. Also, even though people sometimes blamed their romantic partner for their poor night's sleep (i.e., he or she was snoring all night), after taking this into account, poor sleep was still linked to more conflict the next day.

Sleep quality didn’t just impact whether or not romantic partners argued. It also impacted how romantic partners experienced conflict and whether they were successful at resolving the conflict. In a second study, couples came into the lab and were videotaped having a discussion about a source of conflict in their relationship. People who reported having a poorer sleep the night before felt worse during the conflict (they experienced more negative emotions and fewer positive emotions), and were less accurate at reading their partner’s emotions.

Related: Don't Go To Bed Angry (And Good Luck Getting a Good Night’s Sleep If You Do)

When people slept worse than they typically did, they were more likely to argue with their partners the next day.

Does this mean everything will be fine if you get a good night’s sleep? Not necessarily. Your partner’s sleep quality affects how you experience conflict in your relationship as well. The partners of people who didn’t get a good night’s sleep also felt worse during the conflict and were less accurate at reading their partner's emotions. As you probably assumed, partners were most successful at resolving conflict when both partners were well rested — but having just one partner who had slept poorly was enough to make conflict resolution difficult.

So what is the take home message?

Sleep is important, not only for your physical health and work productivity, but for your relationship. Getting a good night’s sleep might make you less likely to argue with your partner and more likely to resolve any conflict that does arise. But, there may be times in your relationship when getting a good night’s sleep is challenging, like when you have a new baby, or when you are facing a looming project deadline at work. Keep in mind that days when you or your partner are overtired are not the best times to attempt to resolve an important source of conflict in your relationship.

We also don't yet know why poor sleep leads to more conflict — it may be that people are simply more grumpy when they haven't slept well, or it is possible that when we're tired, we're overly focused on ourselves and have less energy to try to understand our partner's perspective. Either way, it's probably best to discuss important relationship issues when you're both well rested. Sweet dreams!

Next: Is Sleeping Separately Bad For Our Relationship?

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