Objective: To assess the possibility of preventing cardiac or cutaneous manifestations of neonatal lupus erythematosus or treating the fetus with congenital heart block by administering corticosteroid therapy to the mother.
Methods: Eighty-seven offspring of 40 anti-Ro/SSA-positive mothers, followed up from 1979 to 1996, were evaluated. Autoantibodies against Ro/SSA and La/SSB antigens were detected by immunodiffusion and enzyme-linked immunosorbent assay.
Results: None of 26 neonates whose mothers received corticosteroid maintenance therapy initiated before 16 weeks' gestation demonstrated congenital heart block, whereas 15 of 61 neonates whose mothers received no corticosteroids during pregnancy or began receiving steroid therapy after 16 weeks' gestation had congenital heart block. Complete congenital heart block, once developed, did not respond to corticosteroid treatment in utero. Four infants whose mothers received steroid treatment before 16 weeks' gestation had skin lesions of neonatal lupus erythematosus.
Conclusion: Once established, complete congenital heart block was irreversible and maternal corticosteroid therapy did not effectively prevent cutaneous lupus erythematosus. However, prenatal maintenance therapy with prednisolone or betamethasone given to the mother starting early in pregnancy (before 16 weeks' gestation) might reduce the risk of developing antibody-mediated congenital heart block in the offspring.