Men who are married contribute less around the home than live-in boyfriends, a study by researchers at George Manson University has revealed.
This was found to be the case for the majority of more than 8,000 couples in 28 countries
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And this pattern has enabled researchers to draw some conclusions about the effect of marriage on relationship equalities.
They claim that marriage changes the division of labour towards that of the roles stereotyped as being male and female.
Shannon Davis, lead researcher, said: "Marriage as an institution seems to have a traditionalising effect on couples - even couples who see men and women as equal."
"Our research suggests that couples across many countries are influenced by similar factors when deciding how to divide the housework.
"It's the way society has defined what being married means, the institution itself, that affects behaviour."
The research took a "snapshot" of how couples divided chores, rather than following couples over time to determine how marriage changes who does the housework.
