Availability of Telehealth-Delivered Buprenorphine Treatment for Pregnant and Postpartum Women with Opioid Use Disorder: A Mixed Methods Study - Abstract The opioid crisis continues to be an urgent and pressing national public health emergency, and pregnant and postpartum women (PPW) are especially vulnerable. Between 2010 and 2017, the number of women with opioid-related diagnoses at delivery increased by 131%, and opioid overdose is now a leading and preventable cause of maternal mortality. Uptake of treatment for perinatal OUD can increase the likelihood of a healthy pregnancy and postpartum period for the mother-infant dyad. Despite the safety and effectiveness of medications for OUD (MOUD) – specifically buprenorphine and methadone – during the perinatal period, only half of pregnant women with OUD receive MOUD. Because buprenorphine is available in outpatient settings and requires fewer in-person visits, it is often a more accessible treatment option than methadone, but many PPW with OUD face substantial barriers to receiving this lifesaving treatment, including a lack of providers, stigma, long wait times for appointments, insurance and payment barriers, and transportation and childcare challenges. Telehealth delivery of buprenorphine treatment (telebup) has significant potential to mitigate many of these barriers to in-person OUD care and improve treatment retention and health outcomes for PPW with OUD. Policies regulating the use of telebup have evolved considerably since 2020, and despite preliminary evidence showing treatment success for PPW who are able to access care via a dedicated telehealth OUD program, the extent to which this transformative change in treatment delivery has impacted the accessibility, delivery, and quality of care that PPW with OUD can and do receive is unknown. Further, the impact of telehealth policy changes on access to telebup among PPW – and the extent to which these impacts vary by provider and community characteristics – remains poorly understood. As the opioid crisis continues and many telehealth flexibilities are made permanent, it is critical that public health officials, policymakers, and practitioners better understand the real experiences of PPW with OUD seeking treatment, which will allow decisionmakers to strategically invest in and strengthen local OUD treatment infrastructure. In the proposed mixed-methods study, we will (1) Conduct a longitudinal secret shopper survey of a nationally representative sample of substance use disorder treatment facilities, mental health treatment facilities, and office-based providers to determine the availability of telebup for OUD, overall and by insurance status (private, Medicaid, no insurance); (2) Estimate the association between state-level policies around perinatal OUD treatment, including telehealth and perinatal substance use policies, on telebup availability to PPW with OUD, overall and by provider and county characteristics and over time; and (3) Conduct key informant interviews with providers of telebup and patients with lived experience of perinatal OUD to qualitatively examine facilitators of and barriers to telebup access and identify actionable strategies to expand access to telebup care and improve health outcomes of PPW with OUD.