Findings of a new study suggest that using prescription narcotic painkillers during pregnancy, a common practice, could increase the chances of a small baby or a premature baby. Or else lead to painful drug withdrawal. Called opioids, these prescription painkillers include drugs like hydrocodone (Vicodin), oxycodone (Oxycontin), codeine and morphine.

30% of the pregnant women in Tennessee were found to be using at least one of these prescription drugs. The risks associated with their usage were found to go up if they also smoked or took antidepressants in addition to these.

Lead author of the study, Dr. Stephen Patrick, who is a neonatologist and assistant professor of pediatrics at Vanderbilt University in Nashville expressed surprise at the number of women put on opioid pain relievers during pregnancy.

“I was also surprised by how commonly women smoked in pregnancy, and how much that increased the risk of neonatal abstinence syndrome among those who also used opioid pain relievers in pregnancy,” he said.

Prescription painkiller abuse among pregnant women has risen significantly over the last few years. According to previous findings, the percentage of women taking such drugs during pregnancy has doubled over the past 15 years. This has led to concerns regarding its effects on newborns among experts.

Most pregnant women were found to be using short-acting medications, like hydrocodone or oxycodone. Only 3 percent were on maintenance therapy for addiction to illegal narcotics, such as heroin.

“Some women need to take opioids in pregnancy to improve their infant’s outcome,” Patrick said. “For women with opioid dependency, we know that use of maintenance opioids like methadone decrease rates of preterm birth compared to heroin. For these women, neonatal abstinence syndrome may occur in their infants, but it is much better than the alternative, which is preterm birth.”

Researchers in this case analyzed the medical records of more than 112,000 women on the Tennessee Medicaid program between 2009 and 2011. 28% of these pregnant women filled a prescription for at least one narcotic painkiller.