Could sleeping late be the reason behind your relationship problems?

So you've done the seven-day challenge with your partner, and you've even managed to strike some sort of balance between your hectic work schedule and your relationship, but something still doesn't feel right.

What more, you ask, can you do to rekindle the spark?

It may be time to go back to basics and review your bed habits. More specifically, your sleeping patterns.

Clocking in some late nights at work (or at the bar)? Based on new research, this might well be the reason for your relationship woes.

According to this study published in The Journal of Family Psychology, couples are more likely to feel unhappy or frustrated with their partner if they get less than the recommended seven-and-a-half hours of sleep a day.

For the study in question, a group of 68 newlyweds were asked to individually document their sleeping hours and general satisfaction with their relationship every day for a week. Results found that the key to a happier partnership was some quality shut-eye.

So while "ladies night" can be a way of blowing off steam with your girlfriends, the results of a late night might actually be causing more self-perceived tension between you and your partner.

This goes both ways, of course. If your man has been extra cranky recently, don't take it too personally.

The data shows that men were especially prone to feeling dissatisfied with their partner following a night of poor or insufficient sleep. (Pro tip: If you're going to 'fess up about splurging on some quality watches, be sure to do it the day after your man gets a full eight-hour sleep. He might not be too happy about it, but he may be more forgiving!)

Lucky for us, the problem is one that we can easily - and happily - rectify. After all, more sleep may mean a happier relationship and a slimmer waist, too!

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