Researchers from Harvard Medical School in the United States, the Maastricht University Medical Center in the Netherlands and the University of Edinburgh in Scotland examined 30 studies that included about 1.5 million children.
They found that premature children, born before 37 weeks of gestation, were 46 percent more likely to develop asthma or wheezing problems than kids who weren't born prematurely.
"Very premature children, those born before 32 weeks' gestation, faced an even higher estimated risk, almost three times that of children born at full term,” said Jasper Been from Maastricht University.
About 11 percent of children are born prematurely, the study authors said in a report, which was published in the Jan. 28 online edition of the journal PLoS Medicine.
"The current findings do not support prior suggestions that the association between preterm birth and wheezing disorders becomes less prominent with increasing age," the report said. "Instead, the strength of the association was similar across age groups, up to 18 years," which suggests that the effects of preterm birth on the lungs tend to have life-long consequences.
Although the study found an association between premature birth and respiratory problems such as asthma later in life, it did not prove a cause-and-effect relationship.
Each year, nearly 500,000 babies are premature, or preemies. That's 1 of every 8 infants born in the United States. A premature birth is when a baby is born before 37 completed weeks of pregnancy. A full-term pregnancy is 40 weeks.
Important growth and development occur throughout pregnancy, especially in the final months and weeks. Because they are born too early, preemies weigh much less than full-term babies.
They may have health problems because their organs did not have enough time to develop.
Preemies need special medical care in a neonatal intensive care unit, or NICU. They stay there until their organ systems can work on their own.
By Ruchi Singh
reporter
Park Sae-jin
swatchsjp@ajunews.com