Secret to relationship success? Sharing a bottle of wine once a week

Researchers questioned more than 1,500 couples about their relationships and drinking habits.

They found that concordance - where partners have roughly the same amount of alcohol and at the same time - breeds happiness, the Daily Mail reported.

The authors also discovered that satisfaction with domestic life rose with every occasion partners share a tipple.

Women were four times more likely to be happy if they drank at least once a week with their partner than if they never do. Meanwhile, men were more than three times more content.

"A graded association was evident between time spent drinking as a couple and the odds of a couple being happy," the study, by a team from the University of Otago in New Zealand, stated.

"The more frequently a respondent drank with their partner, the more likely they were to report their relationship as happy."

Moderate drinkers who enjoyed alcohol together at least once a week were the most satisfied of all with 91 per cent enjoying each other's company.

Among the same group, love of marital life fell away to 88 per cent where partners coincided between one and three times a month and only 69 per cent where they never shared a drink.

Happiness drops if there is a heavy drinker in the relationship. However, unhappiest of all (54 per cent) were those who never shared a drink even though one half of the pair consumed a lot of alcohol.