This is Sarah Long with the VOA Special English Science Report.
Scientists have reported the first long-term study of children who were born earlier and smaller than normal. The researchers measured the progress of these premature babies compared with normal children.
Maureen Hack of Rainbow Babies and Children's Hospital in Cleveland, Ohio led the twenty-year study. The New England Journal of Medicine published the results.The researchers studied almost five-hundred premature and normal children. The children were born in a poor area of Cleveland between Nineteen-Seventy-Seven and Nineteen-Seventy-Nine.
On average, the premature babies were born in the twenty-ninth week of pregnancy. Thirty-seven weeks of pregnancy is considered full-term. The babies weighed less than one-thousand-five-hundred grams. They were more likely to have serious medical problems including cerebral palsy, blindness and lung disease.
The premature group did worse on intelligence tests than the others. Still, seventy-four percent of them completed high school. Eighty-three percent of the normal group finished high school.
Both groups tested lower than average on intelligence tests. Experts say these results may not represent the rest of the nation. They say children from rich families usually do better on intelligence tests.
The researchers say the study showed that the young people born too soon got into less trouble than the other group. They had fewer problems with alcohol, drugs and crime. The girls had fewer pregnancies. Children of lower intelligence often get involved in risk-taking activities. So the scientists had not expected this result.
Doctor Hack said the medical problems of the premature group did not surprise the researchers. The babies were born before their organs had a chance to fully develop. Blindness and lung disease often threaten premature babies. Some also suffer severe muscular damage.
The researchers say the premature children had unusually protective and careful parents. This may have saved their lives. The researchers also say extremely watchful parents may have prevented the children from getting into trouble.
About forty-thousand premature babies are born each year in the United States. This is about one-percent of the total number of babies born in this country every year.
This VOA Special English Science Report was written by Jerilyn Watson. This is Sarah Long.