Safety of the newer class of opioid antagonists in pregnancy

Question: I have a patient recently confirmed to be 6 weeks pregnant. For the past 6 months she has been treated for an opioid addiction with buprenorphine-naloxone combination. Should I be concerned about her exposure to this drug combination up to this point of the pregnancy? Should I switch her medication to methadone now that she is pregnant? Answer: The limited data on buprenorphine exposure during pregnancy show no increased risk of adverse outcomes in the newborn. There are limited data on naloxone exposure during pregnancy; however, oral use is not expected to be associated with an increased risk of adverse pregnancy outcomes. Physicians treating pregnant women or women who become pregnant while they are stable taking buprenorphine-naloxone treatment are advised to continue this treatment but to consider transition to buprenorphine monotherapy.