Celebrate each birthday as if it's your last, because it could be.

A study of more than 2 million deaths has found people are 14 per cent more likely to kick the bucket on their birthday than any other day of the year.

"We concluded that birthdays end lethally more frequently than might be expected,'' says Dr Vladeta Ajdacic-Gross, who led the Swiss study, published in Annals of Epidemiology.

An analysis of 2.4 million deaths over a 40 year period found on a person's birthday heart attack risk rose by 19 per cent, stroke went up by 21 per cent and there was nearly an 11 per cent increase in cancer deaths.


Among men there was a 35 per cent increase in suicide, slightly less high in women, at 28 per cent, The Independent reported.

There was also a 44 per cent rise in fatal falls on birthdays, with the risk increasing from about four days before a birthday.

The chance of dying on your birthday increases with age - probability rises to 18 per cent by 60.

The researchers say there are two competing explanations for the phenomenon. The postponement theory suggests seriously ill people can somehow hold on until their birthday has passed, as they try to reach the milestone.

However, the researchers say this theory is not supported by their findings. They support the anniversary hypothesis, which maintains it is the event itself that is responsible.

In the case of heart attacks and strokes, for instance, stress may be to blame. Older people, in particular, they suggest, may feel exposed to stress on birthdays. The research indicates that hospital admissions for cardiovascular conditions occur more frequently on birthdays.