Bérard A, et al. - This study entailed the quantification of the association between leflunomide exposure during pregnancy and risk of major congenital malformation (MCM), prematurity, low birth weight (LBW) and spontaneous abortion. Findings demonstrated no association of maternal exposure to leflunomide during pregnancy with statistically significant increased risk of MCMs, prematurity, LBW or spontaneous abortions. However, caution is warranted in the light of the fact that relatively few women were exposed to leflunomide during pregnancy in this cohort.

Methods

• The associations of first-trimester leflunomide exposure and other antirheumatic drug exposures with MCM and spontaneous abortions were studied in a cohort of 289,688 pregnancies in Montreal, Quebec, Canada, from 1998 to 2015.
• Researchers also asessed second or third-trimester leflunomide exposures for associations with prematurity and LBW.
• They used logistic regression model-based generalised estimating equations.

Results

• Findings reported that 51 pregnancies were exposed to leflunomide during the first trimester, and 21 during the second/third trimesters.
• Researchers found that use of leflunomide during the first trimester of pregnancy was not related to the risk of MCM, adjusting for potential confounders (adjusted OR (aOR) 0.97, 95% CI 0.81 to 1.16; 5 exposed cases).
• They did not find any association between second/third-trimester exposure to leflunomide and the risk of prematurity (aOR 4.03, 95% CI 0.91 to 17.85; 7 exposed cases) nor LBW (aOR 1.06, 95%CI 0.90 to 1.25; 8 exposed cases).
• In addition, data showed no relation of pregnancy exposure to leflunomide to the risk of spontaneous abortion (aOR 1.09, 95% CI 0.90 to 1.32; 11 exposed cases).