Scientists say that with increasing numbers of babies surviving premature birth, childhood asthma is set to become a significant health problem.
The research showed that average asthma rates rose to 14% in babies born prematurely, defined as at least three weeks early.
Those born more than three weeks before the usual 40-week pregnancy term were almost 50% more likely than full-term babies to develop asthma. And babies born more than two months early were three times more at risk.
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