17% of female suicides were on Monday

The Office for National Statistics found 16% of male suicides and 17% of female suicides occured on Mondays, compared to 13% on the weekend days.

Researchers said the trend was not solely a result of returning to work as it was replicated for retired people.

Instead, they said the pattern - gleaned from 34,935 deaths from 1993 to 2002 - was likely to be down to a sense of unease over starting something new.

The report identified New Year's Day 2000 as the one with the highest number of suicides - 23 compared to an average of 10 over the period.

The only day during the period studied when there were no suicides at all was Friday 16 March 2001.

On this day the UK was still in the grip of the foot-and-mouth crisis, which led to thousands of farm animals being slaughtered.

It is important to know which people are vulnerable and when

Andy Bell, of the Sainsbury Centre for Mental Health

Report co-author Anita Brock said: "We suggest it could be linked to a theory to do with new beginnings, such as the New Year, a birthday or just the start of a new week."

She added the findings could help service providers deploy resources, saying, for example, the Samaritans or prison service could ensure more staff were on duty on Mondays.

Over the 10 years just over 27,000 men and nearly 8,000 women committed suicide, according to coroners' verdicts.

Weekend

For both men and women the general trend was a fall in the suicide rate as the week went on with both men and women least likely to kill themselves on both days over the weekend.

Andy Bell, of the Sainsbury Centre for Mental Health, agreed the findings could help in the planning of resources.

"It is important to know which people are vulnerable and when. Then we can target resources accordingly.

"For example, we know the first seven days in prison are the riskiest. To have a detailed understanding we must look at all the studies available, and this is one."

Meanwhile, a separate ONS study found the rate of unexplained deaths - including sudden infant deaths - had fallen for the fourth consecutive year.

In 2004 0.41 unexplained deaths were record for every 1,000 live birth compared to 0.55 in 2001.

There was a slight rise in sudden infant deaths in 2004 compared to the previous year, but this was put down to changes in the way deaths were recorded.