This arrangement can have benefits. But it doesn't have to be permanent, and doesn't have to mean the end of intimacy.

Hundreds of years ago, it was common for married couples among the European upper classes to have separate bedrooms. Sleeping separately was a symbol of luxury and status historically reserved for royalty and the very wealthy.

Nowadays, it's common for married couples and other couples in relationships to sleep in the same bed. But sometimes - for reasons from conflicting schedules to snoring to sleep talking - couples might choose to sleep separately in pursuit of a better night's sleep.

This is known as "sleep divorce". Though I prefer the term "sleep separation", as this doesn't have to be a permanent arrangement - but more on that later.

So why might couples choose to sleep separately? And what does the evidence say about the effects on sleep quality if you sleep alone versus with a partner?

Why do couples opt for a sleep separation?

Couples may choose to sleep apart if one partner's sleep is disturbing the other's, or both are disrupting one another. This can happen for a variety of reasons.

These include waking up frequently in...