Chin-chin and happily ever after

If one half of a couple is a heavy drinker, that couple has a greater chance of divorcing than if both partners drink the same amount.

If both spouses are heavy drinkers, the divorce rate is the same as for cases in which both partners drink little, a study found.

However, if one spouse is a heavier drinker than the other, the divorce rate is much higher than for other couples.

Researchers followed more than 600 couples for nine years, from the time of their weddings.

They found that almost 50% of couples in which one partner drinks more than the other end up divorcing, while the divorce rate for other couples is only 30%.

Kenneth Leonard of the University at Buffalo Research Institute on Addictions led the survey.

He said: "Our results indicate that it is the difference between the couple's drinking habits, rather than the drinking itself, that leads to marital dissatisfaction, separation and divorce."

However, he cautioned that heavy drinking in a marriage may still cause negative outcomes.

"While two heavy drinkers may not divorce, they may create a particularly bad climate for their children."