To determine whether children born to women who had juvenile idiopathic arthritis (JIA) had more adverse birth outcomes than children born to mothers who never had JIA.
Our cohort study used data from physician billing and hospitalizations covering the province of Quebec, Canada. We identified all women with JIA with a first-time birth between January 1, 1983, and December 31, 2010, and assembled a control cohort of first-time mothers without JIA from the same administrative data, matching 4:1 for date of first birth, maternal age, and area of residence. We compared outcomes (stillbirth, prematurity, small for gestational age, and major congenital anomalies) in the JIA versus non-JIA groups using logistic regression.
Mean age at delivery was 24.7 years in the JIA group (n = 1681) and 25.0 years for the non-JIA group (n = 6724). Women who had JIA were at higher risk for a premature baby [adjusted relative risk (RR) 1.20, 95% CI 1.01-1.42], a baby small for gestational age (adjusted RR 1.19, 95% CI 1.04-1.37), and a child with a congenital malformation (adjusted RR 6.51, 95% CI 5.05-8.39). Neural tube defects were higher in the JIA offspring: 1.61% (95% CI 1.11-2.33) versus 0.03% (95% CI 0.01-0.11) in the non-JIA group, as were congenital heart defects: 1.07% (95% CI 0.68-1.69) versus 0.58% (95% CI 0.42-0.79).
Most women with JIA will deliver a normal baby, even though they are at higher risk for having a child with adverse birth outcomes. Research is needed to understand pathophysiologic mechanisms and to investigate the effects of medications during childhood and youth on future birth outcomes.