Beyond Methadone Versus Buprenorphine: Emerging Changes in MOUD During Pregnancy and Postpartum

Methadone and buprenorphine remain the foundational medications for opioid use disorder (OUD) during pregnancy, but important changes have occurred in how these medications are formulated, initiated, dosed, and continued. This review summarizes recent developments in OUD pharmacotherapy during pregnancy and postpartum, with attention to the changing fentanyl-dominated opioid environment and to the distinction between medication initiation, continuation, and treatment interruption. Recent pregnancy-specific evidence supports weekly extended-release buprenorphine as an additional treatment option while highlighting important formulation-specific differences among extended-release formulations. Large observational studies provide increasing reassurance regarding buprenorphine-naloxone during pregnancy and weaken the rationale for routine switching to buprenorphine monoproduct. In the fentanyl era, buprenorphine initiation has expanded beyond a single withdrawal-based approach to include high-dose and low-dose strategies, although pregnancy-specific comparative evidence remains limited. For methadone, newer evidence reinforces the importance of pregnancy-related changes in metabolism, split dosing, individualized metabolic assessment in selected patients, and timely stabilization for patients with high opioid tolerance. Emerging data on naltrexone increasingly support continuation in patients already stable on treatment, while initiation during pregnancy remains more selective because of the required opioid-free interval. Across medications, pregnancy and postpartum should be understood as a continuum of treatment. Delivery may require reassessment of medication dose or frequency, particularly for methadone, but should not prompt automatic dose reductions, formulation changes, or treatment interruption. Treatment effectiveness should be evaluated not only through neonatal outcomes but also through withdrawal and craving control, reduction in nonprescribed opioid use, treatment retention, overdose prevention, patient experience, and postpartum continuity. Recent evidence therefore supports a more individualized approach that avoids pregnancy-specific treatment changes without demonstrated benefit.