Plasma TNF-α levels increase during early pregnancy in RM women regardless of outcome, but are higher in secondary than primary RM, which may be partly genetically determined.
Linear mixed models showed that women carrying females versus males exhibited greater stimulated production of IL-6 at each timepoint (ps⩽0.03), TNF-α in early pregnancy (p=0.04), and IL-1β in mid- and late pregnancy (ps⩽0.05).
In both diseases, active disease and tumor necrosis factor inhibitor (TNFi) discontinuation in early pregnancy were identified as risk factors for disease flares during pregnancy.