Shared dreams and ambitions can help make a successful relationship.

But it seems the rather less romantic link of a shared commute can also help.

Married couples are happier if they travel to work in the same direction, says a study. Experts believe it makes couples feel they share wider goals in life.

They say the findings suggest newlyweds should consider choosing a home that requires them both to commute in one direction, rather than one located at the midway point between their two work places.

"Couples' marital satisfaction can depend on whether they commute to work in the same or different directions," said lead researcher Irene Huang, from the Chinese University of Hong Kong.

"Physically moving in a particular goal-relevant direction (e.g. commuting to work) might become associated with more general goal-related concepts."

They quote the French writer Antoine de Saint-Exupéry, author of The Little Prince, who said: "Love does not consist in gazing at each other, but looking in the same direction together."

The study, published in the Journal of Experimental Social Psychology, involved two surveys of married working adults, with participants asked how happy they were with their marriage and how satisfied they were with their spouse on a scale of one to nine. The first survey involved 280 adults in the US, who were aged 33 on average and had been married for an average of eight years.

Huang and her colleagues found a clear correlation between commuting in the same direction and higher marital satisfaction. They also found that this link existed independent of other factors such as number of years married, number of children, income level and differences in actual time spent commuting.

Furthermore, the link did not depend on whether or not couples sometimes left home for work together, meaning it was not due to having the chance to talk together while commuting.

The second survey involved 139 married adults in Hong Kong, who were 42 years old on average and had been married for an average of 13 years.

It showed a similar correlation to the US results, which also held independent of other relevant factors.