Attention pregnant women: No, you cannot spring the baby early because you're tired of swelling, heartburn and frequent trips to the bathroom. Yet another study shows that being born even a few weeks early is not healthy for the baby. In the new study, babies born between 34 and 37 weeks of gestation, called late preterm, are more likely to have severe respiratory illness compared with those born full term.

Researchers looked at data from 233,844 U.S. deliveries from 2002 to 2008. They found respiratory distress syndrome, a serious lung disease in which babies struggle to breathe and take in sufficient oxygen, occurred in 10.5% of the babies born at 34 weeks, compared with 0.3% of those born at 38 weeks. The late preterm babies also had a higher risk of rapid breathing, pneumonia and respiratory failure.

"The results of our study support the recommendation that every effort should be made to delay delivery of infants until at least 38 weeks' gestational age to decrease respiratory morbidity," the authors wrote.

Last month, another study found that being born even a week or two early was associated with a higher risk of needing special education services at school age. Many other studies also suggest that birth before 39 weeks increases the risk of learning disabilities. Earlier this month, experts writing in the journal Obsteterics & Gynecology said it was time to change the terms surrounding childbirth to send a loud and clear message about what "full term" really means. The current definition of a "term" birth is 37 to 41 weeks. But given the range of outcomes between infants born at 37 weeks and those born at 40 weeks, perhaps "term should be reserved for 39 to 41 weeks while "early term" should be applied to babies born in the 37th and 38th weeks.

 -- Shari Roan


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