Academics from the Australian National University tracked the relationships and characteristics of nearly 2,500 couples between 2001 and 2007.
They found the factors that increased the likelihood of marriage breakdown included differences in age, desire for children, work and alcohol and smoking.
Divorce was twice as likely for couples in which the husband was nine or more years older than his wife.
And the same risk applied in marriages in which the man was two or more years younger than his wife.
Couples were twice as likely to split if the wife had a much stronger preference for children or for more of them.
Smoking and drinking rates also contributed to relationship breakdown.
Relationships in which one person smoked and the other did not were between 75 and 90 per cent more likely to end than those of non-smoking couples.
It was a similar story if the wife was a heavier drinker than her husband.
People whose parents were divorced were more likely to call it quits, so too were those who had children born before the marriage.
Couples in which both people had been previously married had a 90 per cent higher chance of splitting than those marrying for the first time.
Unemployment and or perceived financial stress of the husband, but not the wife, also played a role.
Factors that were not important included country of birth, religious background and education levels.
As well as the number and age of children, a woman's employment status and years in paid employment did not play a role.
The study, called What's love got to do with it? estimates that a quarter of relationships will end within six years and 50 per cent by 25 years.
Dr Rebecca Kippen, Professor Bruce Chapman and Dr Peng Yu will present their findings at a Melbourne conference this week.
- AAP
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