Parents do eventually get a pay-off for those sleepless nights, strained finances and the constant worry that children bring.

Researchers have found a strong link between having children and living longer.

And it doesn’t matter whether the children are boys or girls.

By the age of 60, those with children can be expected to live two years longer than the childless.

Previous studies have had conflicting results, some showing nuns and monks tend to live longer than those outside monasteries.

Other research shows that those with families live longer and that there is probably an optimum family size, not too large as to drain resources and impact the health of the parents.

One study found that having four or five children cuts a women’s life after 50 by about 3.5 years.

But researchers suspect that the support provided by children as parents age is important.

The latest research published in the Journal of Epidemiology & Community Health tracked 704,481 men and 725,290 women from age 60 in Sweden.

Age specific risks of death were calculated and compared for each calendar year for people who had had at least one child and for those who were childless.

The risks of death were lower among those who had had at least one child than they were among those who were childless — and more so among men than women.

The one year risk of death for an 80 year old man with a child was 7.4% compared with 8.3% for a childless man of the same age.

At age 60 the difference in the one year risk of death was 0.06% among men and 0.16% among women. By the age of 90 these differences had risen to 1.47% among men and to 1.10% among women.

The researchers say this is an observational study, so no firm conclusions about cause and effect can be drawn.

However, the researchers write: “Our finding that the association grew stronger when parents became older is further in agreement with research suggesting that childless people face support deficits only towards the end of life.”

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