Rheumatoid arthritis and pregnancy

Abstract

Tumour necrosis factor inhibitors (TNFi) and other biologic response modifiers are being increasingly used for the treatment of rheumatoid arthritis (RA) among women of childbearing age, raising concerns regarding the potential safety of inadvertent or intentional exposure of these agents to the developing fetus. TNFi and other biologics whose constructs contain a functional IgGFc piece are actively transported across the placenta during the second and third trimesters of pregnancy. Very little drug passively diffuses to the fetal circulation during the first trimester, when organogenesis occurs. Cumulative data from both the rheumatology and gastroenterology literature suggest that the rate of birth defects following antenatal TNFi exposure does not appear to be higher than that seen in the general population. There are very little data available on pregnancy outcomes following antenatal exposure to other biologic medications for RA. Cumulative evidence suggests that TNFi use during pregnancy carries low risk for teratogenicity. A single case of fatal BCG infection in an exposed neonate following live virus vaccination highlights the potential need to defer live virus vaccines for at least 6 months in exposed neonates until more data of risk factors for infection susceptibility are available.