A new analysis of existing research suggests that premature babies face a higher risk of developing asthma and wheezing disorders when they're older.
Researchers from Harvard Medical School, the Maastricht University Medical Centre in the Netherlands and the University of Edinburgh in Scotland examined 30 studies that included about 1.5 million children.
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They found that premature children (born before 37 weeks of gestation) were 46% more likely to develop asthma or wheezing problems than kids who weren't born prematurely. Full-term birth is generally considered about 40 weeks' gestation.
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, and his colleagues.
Life-long consequences
About 11% of children are born prematurely, the study authors said in the report, which was published in the 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 researchers wrote in the report. "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.
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