The study of 22,000 people from around the world found that British women who cohabited with men before they were married were slightly unhappier than married women, and that the most likely reason was because they had "violated" normal behaviour and had to endure disapproving glances.
The researchers also claimed that one of the possible reasons they were unhappy was because they were "pitied" for failing to persuade their man down the aisle, and they had low self-esteem.
Countries with a strong, traditional view of marriages, such as America, Bulgaria, Brazil and Mexico were places where the correlation between cohabiting and unhappiness was strongest. Women in places with a relaxed outlook, such as Netherlands and Scandinavian countries were equally happy if they were married or cohabiting.
The/Three research was undertaken by three researchers from the University of Cologne in Germany.
The researchers – Olga Stavrova, Professor Detlef Fetchenhauer and Dr Thomas Schlosser – studied data on 22,000 people which recorded how happy they were, how traditional was the society they lived in, and other information.
The researchers found that on a scale from 0 (completely happy) to 7 (completely unhappy) being married as opposed to cohabiting made women up to 1 point happier or 0.5 point less happy, depending on which of the 28 countries was looked at. In Britain, women were about 0.1 point happier if married.
The results will be unveiled at the British Sociological Association annual conference in London on Friday.
The researchers said: “In countries where the social norm with respect to female gender roles is defined in more traditional terms as a wife, women who live with their partners before or instead of marriage can be considered to violate this norm and are more likely to be exposed to social disapproval. Consequently, they are more likely to report lower happiness scores
“Like other norm transgressors – those who jump the queue or do not give a seat to the elderly on public transport, for example – they can be exposed to social informal sanctions such as social disapproval or rejection. For instance, signs of social disapproval may translate in disapprobatory glances of hotel reception staff or a landlord who accidentally comes to know one’s family situation."
The study found that men were not affected by how traditional was their country’s view on the roles of men and women. The researchers say that men’s traditional role as breadwinner is not undermined by their marital status, whether they live in more traditional societies or not.
Controversially, they suggest that not being married leads to women being "pitied and looked down upon".
They said: "We can speculate that in such societies, people tend to believe that a woman lives together with her partner out of wedlock not because she doesn’t want to marry him but because he doesn’t want to marry her.
“The society’s doubts in the commitment of her partner makes a cohabiting woman pitied and looked down upon, which could be detrimental for her self-esteem and psychological wellbeing regardless of her own perception of her partner’s commitment.”