Anti-Ro (SS-A) antibodies and congenital complete heart block

Maternal anti-Ro (SS-A) antibodies have been implicated in the pathogenesis of congenital complete heart block. When congenital complete heart block occurs, SS-A antibodies are almost always present in maternal and fetal serum, although not all infants of SS-A antibody positive mothers are affected. We describe a situation in which antibodies to SS-A were present in high titre in both maternal and fetal serum, although there was no evidence of heart block in the infant. This is the first report of a normal infant in whom maternally derived SS-A antibodies have been documented in high titre.