Emerging data on the use of anti-tumor necrosis factor-alpha medications in pregnancy

Anti-tumor necrosis factor (TNF) α medications are used for the treatment of a number of autoimmune diseases. Evaluation of pregnancy safety for these medications is complicated by the contribution of the underlying maternal disease to adverse pregnancy outcomes, such as preterm delivery and reduced birth weight. Placental transport of these medications is thought to be minimal in the first trimester, thereby providing some reassurance regarding theoretical risks for congenital malformations. Available human exposure data are sparse; however, to date there has been no convincing evidence to support an increased risk for a specific pattern of major congenital malformations with any of the drugs in this group for which some data is currently available. As a result of the improvement of symptoms during pregnancy in some women with autoimmune diseases, it may be possible to discontinue treatment before or shortly after conception. However, in some cases the benefits of treatment and concerns for disease flares in pregnancy have warranted continued treatment during pregnancy. Because of the relatively long half-life of these medications, and theoretical concerns for immune compromise of the infant following exposure in the latter two trimesters, some clinicians recommend discontinuation of treatment in the third trimester to avoid potentially prolonged infant exposure in the postpartum period. Currently ongoing controlled cohort studies for some of the TNF blocker medications will help to provide more definitive answers for clinicians and patients.