Pregnancy Outcomes after Exposure to TNF-α Inhibitors During Pregnancy for the Treatment of Arthritic Diseases: A Meta-Analysis Authors: Mirdamadi K, Salinas T, Vali R, Papadimitripulous M, Piquette-Miller M Background: Auto-immune arthritic diseases affect many women of child-bearing age. Tumor necrosis factor (TNF)-α inhibitors are currently used for the treatment of various immune-mediated diseases during pregnancy. However, there has been no evaluation of safety in the treatment of arthritic diseases during gestation. Objective: To analyze the risk of adverse pregnancy and neonatal outcomes after treatment of arthritic diseases with TNF-α inhibitors. Methods: Major databases including Ovid MEDLINE, Embase, and Web of Science, were searched inclusive to April 2016. Observational prospective cohort studies evaluating pregnancy outcomes after exposure to TNF-α inhibitors for the treatment of arthritic diseases during pregnancy were included. Data on pregnancy and neonatal outcomes was extracted from all included studies. A meta-analysis was performed using inverse-variance random effect with a 95% confidence interval (95%CI) and p<0.05. Results: Eight prospective studies with comparison groups were included in the meta-analysis. TNF-α inhibitors were associated with significantly higher risks of low birth weight (odds ratio (OR), 1.43; 95%CI, 1.00-2.04) and significantly lower rates of live birth (OR, 0.61; 95%CI, 0.38-0.98). However, birth defects, therapeutic abortion, spontaneous abortion, and preterm birth were not significantly different between the two groups. Conclusion: Treatment of arthritic diseases with TNF-α inhibitors during pregnancy increases the risk of lower birth weight and decreases the rate of live birth in this population. While duration of treatment and gestational age at exposure may play a role in these outcomes, evaluation of risk versus benefit is crucial in this patient population. Key words: TNF-α inhibitors, pregnancy outcomes, arthritic disease, meta-analysis.