Pregnant women with opioid use disorder (OUD) are at risk of overdose, infectious diseases, and inadequate prenatal care. Additional risks include adverse pregnancy and infant outcomes, such as preterm birth and neonatal abstinence syndrome. Management and treatment of OUD during pregnancy are associated with improved maternal and infant outcomes. Professional organizations, including the American College of Obstetricians and Gynecologists, recommend offering opioid agonist pharmacotherapy (i.e., methadone or buprenorphine) combined with behavioral therapy as standard treatment for pregnant women with OUD. Other medications and herbal supplements have also been used by pregnant women for OUD. Determining which OUD treatments optimize maternal and infant outcomes is challenging given the host of potential factors that affect these outcomes. The Centers for Disease Control and Prevention initiated the MATernaL and Infant NetworK to Understand Outcomes Associated with Treatment of Opioid Use Disorder during Pregnancy (MAT-LINK) to monitor more than 2000 mothers and their infants, using data collected from geographically diverse clinical sites. Information learned from MAT-LINK will inform the future management and treatment of pregnant women with OUD.