(Portland, OR) -- A new OHSU study finds the use of nicotine and cannabis during pregnancy dramatically increases the rate of infant death. Researchers evaluated hospital data and vital statistics from more than three million pregnant patients with documented substance use. They found that the rate of infant death was four times higher in users of both cannabis and nicotine compared with non-users, and nearly twice as high compared with users of just one of those. Researchers are calling for more research and patient education for better outcomes. The study is published in JAMA Network Open.