A retrospective, observational study on medication for opioid use disorder during pregnancy and risk for neonatal abstinence syndrome

The prevalence of opioid use disorder (OUD) among pregnant women is increasing. Research consistently demonstrates the efficacy of medications for OUD (MOUD); however, researchers have called for additional studies evaluating the safety of MOUD during pregnancy, particularly the relative safety of two commonly used MOUD medications-methadone and buprenorphine. This study aimed to evaluate the consequences of MOUD exposure during pregnancy on risk for neonatal abstinence syndrome (NAS). In a clinical sample of infants born to women with OUD, we evaluated the risk of NAS among those exposed to (i) methadone and (ii) buprenorphine compared with those unexposed to MOUD, as well as the risk of NAS among those exposed to (i) methadone compared with those exposed to (ii) buprenorphine. Compared with buprenorphine-exposed infants (n = 37), methadone-exposed infants (n = 27) were at increased risk for NAS (odds ratio [OR] = 4.67, 95% confidence interval [CI]: 1.03, 21.17). Compared with unexposed infants (n = 43), buprenorphine-exposed infants were at decreased risk for NAS (OR = 0.45, 95% CI: 0.14, 1.39) and methadone-exposed infants were at increased risk for NAS (OR = 2.64, 95% CI: 0.79, 8.76), though these associations were not statistically significant. Our study suggests that when methadone and buprenorphine are equally appropriate options for the treatment of OUD in pregnant women, buprenorphine may add the additional benefit of reduced risk of newborn NAS.