Biologic Disease-Modifying Antirheumatic Drug Use During Pregnancy and Lactation

Autoimmune rheumatic diseases (ARDs) are chronic diseases characterized by periods of flare and remission. Autoimmune rheumatic diseases are often diagnosed in reproductive-aged women, and treatment decisions must factor in pregnancy potential and intent. Well-controlled maternal disease in the prepregnancy period and during pregnancy portends improved maternal and fetal outcomes. Although conventional immunosuppressant and agents remain a mainstay of treatment, use of biologic disease-modifying antirheumatic drugs (bDMARDs), either alone or in combination with conventional agents, is increasingly common. Multiple professional societies have published formal evidence-based guidelines with recommendations for ARD treatment during pregnancy and lactation. This review focuses on the use of bDMARDs during pregnancy and lactation and the safety of infant vaccination after in utero exposure; we synthesize current evidence, summarize guideline recommendations, and present practical management strategies. In general, guidelines support the use of bDMARDs during pregnancy and in the postpartum period to maintain disease control. Among biologic classes, tumor necrosis factor inhibitors have the most robust evidence establishing safety for use during pregnancy and lactation. Safety data for newer agents with differing targets or mechanisms of action are often lacking. Teratogenicity is unlikely; large-molecule monoclonal antibodies do not cross the placenta until after organogenesis. The main concerns with treatment during pregnancy are potential effects on the neonatal immune system and other unknown consequences of in utero exposure. Risks of treatment are often outweighed by benefits, especially for maternal disease refractory to other pregnancy-compatible options. Additional research is needed to inform individualized counseling and shared decision making.