Maternal Cytokines and Disease Severity Influence Pregnancy Outcomes in Women with Rheumatoid Arthritis

Objectives: To assess the influence of maternal cytokine levels, disease activity and severity on preterm delivery, SGA and cesarean delivery in pregnant women with RA. Methods: A prospective study in 47 pregnant women with RA and 22 healthy pregnant controls. The main outcome measures were birth weight in relation to maternal serum levels of interleukin-6 (IL-6), interleukin-10 (IL-10) and RA activity and severity at three different time points: preconception and during the first and third trimesters. Results: During the third trimester, IL-10 was detectable in 23.4% of patients with RA, IL-6 in 76.6%. Mean birth weight born to mothers with RA was higher when IL-10 level was high compared with low (P=0.001), and lower when IL-6 was high compared with low (P=0.035). Also increase in DAS-28 (in 60.1%, P=0.001), HAQ – DI (in 87.5%, P=0.013), and PS (56.9 ? 11.4, P=0.003) associated with increased risk for SGA. High PGS was associated with unfavorable pregnancy outcome (preterm, SGA, and C.S).Conclusion: High maternal IL-10 levels are associated with higher birth weight and high IL-6 levels are associated with lower birth weight (SGA). Among women with RA, disease activity and severity are predictive of unfavorable pregnancy outcomes suggesting that better disease management early in the pregnancy could improve pregnancy outcomes.