Babies who are very small at birth are far more likely to have long-term health and educational problems than babies born at a normal weight, according to new research.
The US study focused on 219 extremely low birth weight children born between 1992 and 1995 at a hospital in Cleveland, Ohio.
Researchers compared the children, now aged eight to 176 eight-year-olds who were a normal weight at birth and who attended the same schools and were the same race and sex.
The study found that the low-birth weight children had high rates of such chronic conditions as asthma, cerebral palsy and blindness as well as poorer academic achievement and motor and social skills.
The researchers say their study underlines the extraordinary costs of care that will be needed to manage the medical, educational and other service needs of extremely low-birth weight children with chronic conditions.
Dr Jon Tyson of the University of Texas Health Science Center said it had been hoped that improved survival of even the smallest infants would translate into fewer disabilities or other long-term problems, according to the Health and Behavior website.
However, if anything the new findings may understate the problems of extremely low birth-weight children compared with normal-weight children.
The research is published in the The Journal of the American Medical Association.