Association of fetal heart block and massive placental infarction due to maternal autoantibodies.

Two different effects of maternal autoantibodies presented in a third-trimester pregnancy. The first was complete fetal heart block, demonstrated ultrasonographically, which correlated with the presence of anti-Ro and anti-La antibodies in the maternal serum. The second effect was decidual vasculopathy and thrombosis, a morphologic finding in the placenta that caused massive placental infarction and intrauterine death. The placental pathology correlated with the presence of anticardiolipin antibodies in the maternal serum at the time of stillbirth.