Health News -- Maternal use of prescription opioid pain relievers during early pregnancy or just prior to conception has been linked to an increased risk of birth defects. According to a new U.S. government report, expectant mothers who take painkillers such as codeine, hydrocodone or oxycodone (Oxycontin) put their newborns at greater risk of certain birth defects. The details of the report can be found in the American Journal of Obstetrics & Gynecology.