Increased risk of congenital malformations in offspring born to women with systemic lupus erythematosus in South Korea: a nationwide population-based study

OBJECTIVES: The aim of this study was to determine the risk of congenital malformations in offspring born to women with systemic lupus erythematosus (SLE). METHODS: This nationwide population-based study included Korean women who had a singleton pregnancy. The risk of congenital malformations in women with SLE was compared with those without SLE. Multivariable analyses were performed to estimate the OR of congenital malformations. In a sensitivity analysis, the risk of malformation was compared between the offspring of women with SLE and those of propensity-matched women without SLE. RESULTS: Of a total of 3 279 204 pregnant women, 0.1% had SLE and their offspring had a higher frequency of congenital malformations (17.13% vs 11.99%, p<0.0001). After adjustment for age, parity, hypertension, diabetes, and fetal sex, the SLE group was found to be associated with an increased risk of congenital malformations in the nervous system (adjusted OR (aOR, 1.90; 95% CI, 1.20 to 3.03), eye, ear, face, and neck (aOR, 1.37; 95% CI, 1.09 to 1.71), circulatory system (aOR, 1.91; 95% CI, 1.67 to 2.20), and musculoskeletal system (aOR, 1.26; 95% CI, 1.05 to 1.52). Even after propensity matching, some of the tendencies were maintained. CONCLUSIONS: This nationwide population-based study in South Korea indicates that compared with the general population, neonates born to SLE mothers have a slightly increased risk of congenital malformations affecting the nervous system, head and neck, cardiovascular system, and musculoskeletal system. When a woman with lupus becomes pregnant, careful fetal ultrasound and newborn screening can be helpful in identifying the risk of potential malformations.