The safety of biologic agents during pregnancy is still being investigated. Tumor necrosis factor α (TNF-α) inhibitors are the only well-studied biological drugs in pregnancy; they do not appear to be teratogenic but increase the risk of infection after birth when given in late pregnancy. The long-term effects in exposed children are, at present, unknown. An increased risk of infection is a concern for all biologics and the risk increases further should combination with glucocorticoids be necessary. Experiences with rituximab, abatacept, anakinra, tocilizumab, and belimumab in pregnancy are limited. These drugs should be avoided during pregnancy or used only when no other option is available for treatment of serious maternal disease.