April 30, 2012 (CHICAGO) --Disturbing new research says the number of U.S. babies born with signs of opiate drug withdrawal has tripled in a decade. Researchers say it's because many more pregnant women are using legal and illegal narcotics, including vicodin, oxycontin and heroin. They stress this also includes women who were taking prescribed painkillers for legitimate reasons. The first national study of the problem has been released online in the 'Journal of the American Medical Association.' Weaning the infants from the drugs can take weeks of months and often require a long stay in intensive care units.