Being small for gestational age (SGA) - significantly smaller than most babies born after the same number of weeks of pregnancy - was a greater risk factor for future hospitalisation than preterm birth, Dr Katarina Ekholm Selling of Linkoping University and her colleagues found.

While the early-life health consequences of SGA and preterm birth have been investigated extensively, there has been less research on how these individuals fare later in life, Selling noted in an interview with Reuters Health.

To investigate, she and her team looked at the hospitalisation records between 1987 and 1996 for every person born in Sweden between 1973 and 1975, a total of 304,275 men and women.

Overall, SGA men and women were 16 per cent more likely to be hospitalised than individuals who were born at a normal size, while having been born preterm increased hospitalisation risk by 6 per cent.

People who had been both SGA and preterm were 42 percent more likely to be hospitalised.

Hospitalisations for mental disorders, drug use, injuries and poisoning, as well as 'symptoms, signs and ill-defined conditions,' poorly defined intestinal infections and genitourinary diseases, were more frequent for SGA individuals.

Those born preterm were more likely than full-term infants to be hospitalised for endocrine, nutritional and metabolic diseases, mental disorders and nervous system diseases, birth defects and 'symptoms, signs and ill-defined conditions.'

While the study was not designed to show the mechanism behind the increased risk of hospitalisation for SGA and preterm individuals, Selling said, the greater likelihood of accidents, drug use and mental health problems seen with SGA suggest that 'personality may be the key.'

One possibility could be that SGA individuals are more prone to risk-taking behavior, she added, but studies investigating the relationship have had conflicting results.

SGA and preterm individuals also tend to be from more disadvantaged socioeconomic backgrounds, Selling said, and while her team attempted to use statistical techniques to control for the effect of socioeconomic status, it may still be involved in the relationship.

Nevertheless, she pointed out, 'there are many other factors that are far more important in determining our health in later life than being born small for gestational age.' -- REUTERS