According to researchers women who have their babies very close together, along with women who never have children, are at risk of an earlier death and poorer health in later life.

In a study, funded by the Economic and Social Research Council, it has been found that mothers who had less than 18 months between births faced up to a 20 per cent higher risk of early death compared with those with longer gaps.

The researchers attribute this to the strains of having to look after a number of young children of a similar age.

The study however also found that childless women had a 20 per cent higher risk of death as they got older when compared with women with two children.

Most at risk appear to be women with five or more children who face between a 12 and 25 per cent higher risk of death than those who had given birth twice.

Teenage mothers also faced between a 15 and 30 per cent higher mortality risk compared with those who gave birth after the age of 20 and were also found to have more depression and respiratory disease.

Professor Emily Grundy, from the Centre of Population Studies at the School of Hygiene and Tropical Medicine in London, who led the research, says there is no single reason for the increased health risks faced by these groups of women, but it appears that people’s life choices have a cumulative effect on their health in old age.

Professor Grundy examined information on thousands of women in the UK and the United States, and suggests that one explanation for the higher death rates among childless women might be that ill-health leads them not to have children in the first place.

Grundy says women with five or more children might suffer poorer health as a result of the extra strains on the body and they may also have less money to look after their own health.

The findings have been revealed in an analysis of population-wide studies monitoring many thousands of women in the UK and US, the largest data set of which covered 1% of the population of England and Wales born between 1911 and 1940.

Another British survey from the Medical Research Council included detailed information about 1,500 women born in 1946.

The third study, from the US, tracked changes in health, employment, income and wealth for about 10,000 people born between 1931 and 1941.