One baby is born every hour with symptoms of opiate withdrawal. That's about 13,500 drug-addicted infants a year signaling a sharp rise over the last decade, according to a new study published in the Journal of the American Medical Association. Newborns whose mothers abuse prescription painkillers during pregnancy may experience "neonatal abstinence syndrome," which can lead to seizures, breathing problems, dehydration, feeding difficulties and other health issues. Babies with this condition are usually born small and require extensive nursing care; doctors use methadone therapy, slowly reducing the dosage over time to avoid extreme withdrawal symptoms, which can be fatal. Treatment for these infants cost up to $720 million in 2009, with most cases covered by Medicaid. “The incidence has gone crazy and I think it has the potential to become a national or international issue,” says Marie J. Hayes, a clinical neuroscientist at the University of Maine. She notes that the general surge in prescription drug abuse is responsible: “[mothers] who previously might not have used heroin or the needle are more likely to use prescription opiates.” From 2000 to 2009, the number of pregnant women using and abusing opiates has increased fivefold and the number of infants born with neonatal abstinence syndrome tripled. Many mothers reportedly claim they didn’t realize prescription painkillers could harm their child—because they're legal.