Besides yanking the duvet from each other during the night, the second reason for a night-time squabble is the age-old of problem of snoring.
One in ten couples claim to have an argument over the nightly affliction at least twice a week - with over half of respondents blaming men as the worst culprits for snoring.
However 39 per cent said both sexes were as bad as each other, according to the poll by hotel chain to coincide with National Snoring Week.
Also, an average couple apparently bicker in the bedroom 167 times a year.
Other bedroom disputes include whingeing about being too hot, allowing the kids to sleep in the bed and not being ‘in the mood’.
“Our research shows most of the arguments couples have in the bedroom are down to habits that are easy to resolve as a relationship develops,” a major newspaper quoted an owner of the major hotel chain, as saying.
“We conducted this research to coincide with National Stop Snoring Week and the findings discovered that a lot of people are seriously affected by snoring and hogging the duvet.
“People suffer from snoring to varying degrees and the research shows how something like snoring can impact on our day to day lives especially if one person in the relationship is missing out on much needed sleep.”
The poll also revealed that the average Brit is disturbed nearly twice a week by their partners snoring, but one night a week they even wake themselves up with their own heavy breathing.
The survey took into consideration 2,000 people all of whom are in a relationship. Of those exactly half said that their other half snored.
Other issues which lead to disagreements in the boudoir include allowing children to sleep in the marital bed and venturing on to the wrong side.
Being touched by freezing cold feet is also likely to cause tension because of the bedroom being too chilly.
The time at which couples go to bed, leaving lights on to read and leaving drinks on the bedside table were also likely to trigger a spat.
But it’s no wonder there is confusion - cuddling for too long can cause problems in a relationship, as can not cuddling for long enough.